Magnetic head and magnetic recording device

Abstract

To provide a magnetic head and a magnetic recording device capable of improving recording density.SOLUTION: According to the embodiment, a magnetic head includes: first and second magnetic poles; and a laminate which is provided between the first and second magnetic poles. The laminate includes: a first magnetic layer; a second magnetic layer which is provided between the first magnetic layer and the second magnetic pole; a first non-magnetic layer which is provided between the first magnetic layer and the second magnetic layer; a second non-magnetic layer which is provided between the second magnetic layer and the second magnetic pole; and a third non-magnetic layer which is provided between the first magnetic pole and the first magnetic layer. The first magnetic layer contains a first element containing at least any one of Fe, Co, and Ni. The second magnetic layer contains (Fe100-xCox)100-yEy (where 10 atm%≤x≤50 atm% and 10 atm%≤y≤90 atm%). A second element E contains at least one selected from a group consisting of Cr, V, Mn, Ti, and Sc. The first magnetic layer does not contain the second element. Alternatively, the concentration of the second element at the first magnetic layer is lower than the concentration of the second element at the second magnetic layer.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present invention relates to a magnetic head and a magnetic recording device. [Background technology]

[0002] 2. Description of the Related Art A magnetic head is used to record information on a magnetic recording medium such as a hard disk drive (HDD). It is desirable to improve the recording density in magnetic heads and magnetic recording devices. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2008-277586 A Summary of the Invention [Problem to be solved by the invention]

[0004] The embodiments of the present invention provide a magnetic head and a magnetic recording device that enable improvement in recording density. [Means for solving the problem]

[0005] According to an embodiment of the present invention, a magnetic head includes a first magnetic pole, a second magnetic pole, and a laminate provided between the first magnetic pole and the second magnetic pole. The laminate includes a first magnetic layer, a second magnetic layer provided between the first magnetic layer and the second magnetic pole, a first non-magnetic layer provided between the first magnetic layer and the second magnetic layer, a second non-magnetic layer provided between the second magnetic layer and the second magnetic pole, and a third non-magnetic layer provided between the first magnetic pole and the first magnetic layer. The first magnetic layer includes a first element including at least one of Fe, Co, and Ni. The second magnetic layer includes a first element including at least one of (Fe 100-x Co x ) 100-y E y(10 atm%≦x≦50 atm%, 10 atm%≦y≦90 atm%). The second element E includes at least one selected from the group consisting of Cr, V, Mn, Ti, and Sc. The first magnetic layer does not include the second element, or the concentration of the second element in the first magnetic layer is lower than the concentration of the second element in the second magnetic layer. [Brief description of the drawings]

[0006] [Figure 1] 1A and 1B are schematic views illustrating the magnetic head according to the first embodiment. [Diagram 2] FIG. 2 is a schematic cross-sectional view illustrating the magnetic recording device according to the first embodiment. [Diagram 3] FIG. 3 is a graph illustrating the characteristics of the magnetic head. [Figure 4] 4(a) and 4(b) are graphs illustrating the characteristics of the magnetic head. [Diagram 5] FIG. 5 is a graph illustrating the characteristics of the magnetic head. [Figure 6] 6A and 6B are schematic plan views illustrating the magnetic head according to the first embodiment. [Figure 7] 7A and 7B are schematic views illustrating the characteristics of the magnetic head according to the embodiment. [Figure 8] FIG. 8 is a schematic view illustrating the characteristics of the magnetic head according to the first embodiment. [Figure 9] 9(a) and 9(b) are graphs illustrating the characteristics of the magnetic layer included in the magnetic head. [Figure 10] FIG. 10 is a graph illustrating the characteristics of the magnetic layer included in the magnetic head. [Figure 11] FIG. 11 is a graph illustrating the characteristics of the magnetic layer included in the magnetic head. [Figure 12] FIG. 12 is a schematic cross-sectional view illustrating a portion of the magnetic recording device according to the second embodiment. [Figure 13]13A and 13B are schematic views illustrating the characteristics of the magnetic recording device according to the embodiment. [Figure 14] 14(a) to 14(c) are schematic views illustrating the characteristics of the magnetic recording device according to the second embodiment. [Figure 15] FIG. 15 is a schematic diagram illustrating the characteristics of a magnetic recording device. [Figure 16] FIG. 16 is a schematic cross-sectional view illustrating a portion of the magnetic recording device according to the second embodiment. [Figure 17] FIG. 17 is a schematic cross-sectional view illustrating a portion of the magnetic recording device according to the second embodiment. [Figure 18] FIG. 18 is a schematic cross-sectional view illustrating a portion of the magnetic recording device according to the third embodiment. [Figure 19] FIG. 19 is a schematic diagram illustrating the characteristics of a magnetic recording device. [Figure 20] FIG. 20 is a schematic cross-sectional view illustrating a portion of the magnetic recording device according to the third embodiment. [Figure 21] FIG. 21 is a graph illustrating the characteristics of the magnetic layer included in the magnetic head. [Figure 22] FIG. 22 is a graph illustrating the characteristics of the magnetic layer included in the magnetic head. [Diagram 23] FIG. 23 is a schematic cross-sectional view illustrating the magnetic head according to the fourth embodiment. [Figure 24] FIG. 24 is a schematic cross-sectional view illustrating an experimental sample. [Diagram 25] FIG. 25 is a graph illustrating the experimental results. [Figure 26] 26(a) to 26(c) are schematic views illustrating the magnetic head according to the fourth embodiment. [Figure 27] FIG. 27 is a schematic cross-sectional view illustrating the magnetic head according to the fourth embodiment. [Figure 28] FIG. 28 is a schematic cross-sectional view illustrating the magnetic head according to the fourth embodiment. [Figure 29]FIG. 29 is a schematic cross-sectional view illustrating a part of the magnetic recording device according to the fifth embodiment. [Diagram 30] FIG. 30 is a schematic view illustrating the characteristics of the magnetic recording device according to the fifth embodiment. [Diagram 31] FIG. 31 is a schematic diagram illustrating the characteristics of a magnetic recording device. [Diagram 32] 32(a) to 32(c) are schematic cross-sectional views illustrating the characteristics of the magnetic recording device according to the fifth embodiment. [Diagram 33] FIG. 33 is a schematic cross-sectional view illustrating a part of the magnetic recording device according to the sixth embodiment. [Diagram 34] FIG. 34 is a schematic cross-sectional view illustrating the magnetic head according to the embodiment. [Diagram 35] FIG. 35 is a schematic perspective view illustrating the magnetic recording device according to the embodiment. [Diagram 36] FIG. 36 is a schematic perspective view illustrating a part of the magnetic recording device according to the embodiment. [Figure 37] FIG. 37 is a schematic perspective view illustrating the magnetic recording device according to the embodiment. [Figure 38] 38A and 38B are schematic perspective views illustrating a part of the magnetic recording device according to the embodiment. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0007] Hereinafter, embodiments of the present invention will be described with reference to the drawings. The drawings are schematic or conceptual, and the relationship between the thickness and width of each part, the size ratio between parts, etc. are not necessarily the same as those in reality. Even when the same part is shown, the dimensions and ratios of each part may be different depending on the drawing. In this specification and each drawing, elements similar to those described above with reference to the previous drawings are given the same reference numerals and detailed descriptions thereof will be omitted as appropriate.

[0008] (First embodiment) 1A and 1B are schematic views illustrating the magnetic head according to the first embodiment. Fig. 1(a) is a cross-sectional view, and Fig. 1(b) is a plan view seen from the arrow AR1 in Fig. 1(a). FIG. 2 is a schematic cross-sectional view illustrating the magnetic recording device according to the first embodiment. 2, a magnetic recording device 210 according to the embodiment includes a magnetic head 110 and an electric circuit 20D. The magnetic recording device 210 may include a magnetic recording medium 80. At least a recording operation is performed in the magnetic recording device 210. In the recording operation, information is recorded on the magnetic recording medium 80 using the magnetic head 110.

[0009] The magnetic head 110 includes a recording section 60. As described below, the magnetic head 110 may also include a reproducing section. The recording section 60 includes a first magnetic pole 31, a second magnetic pole 32, and a laminate 20. The laminate 20 is provided between the first magnetic pole 31 and the second magnetic pole 32.

[0010] For example, the first magnetic pole 31 and the second magnetic pole 32 form a magnetic circuit. The first magnetic pole 31 is, for example, a main magnetic pole. The second magnetic pole 32 is, for example, a trailing shield. The first magnetic pole 31 may be the trailing shield and the second magnetic pole 32 may be the main magnetic pole.

[0011] The direction from the magnetic recording medium 80 to the magnetic head 110 is defined as the Z-axis direction. One direction perpendicular to the Z-axis direction is defined as the X-axis direction. A direction perpendicular to the Z-axis direction and the X-axis direction is defined as the Y-axis direction. The Z-axis direction corresponds to the height direction, for example. The X-axis direction corresponds to the down-track direction, for example. The Y-axis direction corresponds to the cross-track direction, for example. The magnetic recording medium 80 and the magnetic head 110 move relatively along the down-track direction. A magnetic field (recording magnetic field) generated by the magnetic head 110 is applied to a desired position on the magnetic recording medium 80. The magnetization of the desired position on the magnetic recording medium 80 is controlled to a direction according to the recording magnetic field. As a result, information is recorded on the magnetic recording medium 80.

[0012] The direction from the first magnetic pole 31 to the second magnetic pole 32 is defined as a first direction D1. The first direction D1 is substantially along the X-axis direction. In an embodiment, the first direction D1 may be inclined at a small angle with respect to the X-axis direction.

[0013] As shown in FIG. 2, a coil 30c is provided. In this example, a portion of the coil 30c is between the first magnetic pole 31 and the second magnetic pole 32. In this example, a shield 33 is provided. In the X-axis direction, the first magnetic pole 31 is between the shield 33 and the second magnetic pole 32. Another portion of the coil 30c is between the shield 33 and the first magnetic pole 31. An insulating portion 30i is provided between these multiple elements. The shield 33 is, for example, a leading shield. The magnetic head 110 may include a side shield (not shown).

[0014] 2, a recording current Iw is supplied to the coil 30c from the recording circuit 30D. A recording magnetic field corresponding to the recording current Iw is applied to the magnetic recording medium 80 from the first magnetic pole 31.

[0015] 2, the first magnetic pole 31 includes a medium facing surface 30F. The medium facing surface 30F is, for example, an air bearing surface (ABS). The medium facing surface 30F faces, for example, the magnetic recording medium 80. The medium facing surface 30F is along, for example, the XY plane.

[0016] 2, the electric circuit 20D is electrically connected to the laminate 20. In this example, the laminate 20 is electrically connected to the first magnetic pole 31 and the second magnetic pole 32. A first terminal T1 and a second terminal T2 are provided on the magnetic head 110. The first terminal T1 is electrically connected to the laminate 20 via the first wiring W1 and the first magnetic pole 31. The second terminal T2 is electrically connected to the laminate 20 via the second wiring W2 and the second magnetic pole 32. For example, a current (for example, a direct current) is supplied to the laminate 20 from the electric circuit 20D.

[0017] 1(a) and 1(b), the stack 20 includes a first magnetic layer 21, a second magnetic layer 22, a first non-magnetic layer 41, a second non-magnetic layer 42, and a third non-magnetic layer 43. In FIGS. 1(a) and 1(b), the insulating portion 30i is omitted.

[0018] The second magnetic layer 22 is provided between the first magnetic layer 21 and the second magnetic pole 32. The first non-magnetic layer 41 is provided between the first magnetic layer 21 and the second magnetic layer 22. The second non-magnetic layer 42 is provided between the second magnetic layer 22 and the second magnetic pole 32. The third non-magnetic layer 43 is provided between the first magnetic pole 31 and the first magnetic layer 21.

[0019] For example, the third non-magnetic layer 43 may be in contact with the first magnetic pole 31 and the first magnetic layer 21. The first non-magnetic layer 41 may be in contact with the first magnetic layer 21 and the second magnetic layer 22. The second non-magnetic layer 42 may be in contact with the second magnetic layer 22 and the second magnetic pole 32.

[0020] At least one of the first non-magnetic layer 41, the second non-magnetic layer 42, and the third non-magnetic layer 43 includes a third element. The third element includes, for example, at least one selected from the group consisting of Cu, Au, Cr, V, Al, and Ag. In a non-magnetic layer including such a material, for example, a high spin transmittance is obtained. For example, a high oscillation intensity is obtained.

[0021] At least one of the second nonmagnetic layer 42 and the third nonmagnetic layer 43 may contain a fourth element. The fourth element includes, for example, at least one selected from the group consisting of Ru, Ir, Ta, Rh, Pd, Pt, and W. In a nonmagnetic layer including such a material, for example, a low spin transmittance is obtained. For example, stable oscillation is easily obtained. At least one of the second nonmagnetic layer 42 and the third nonmagnetic layer 43 may include the above-mentioned third element and fourth element.

[0022] In the first embodiment, the first magnetic layer 21 includes a first element. The first element includes at least one of Fe, Co, and Ni.

[0023] The second magnetic layer 22 includes a first element and a second element. The second element includes at least one selected from the group consisting of Cr, V, Mn, Ti, and Sc. The first magnetic layer 21 does not include the second element. Alternatively, the concentration of the second element in the first magnetic layer 21 is lower than the concentration of the second element in the second magnetic layer 22.

[0024] For example, the concentration of the second element in the second magnetic layer 22 is 10 atomic % or more and 80 atomic % or less. The second magnetic layer 22 containing such a material has, for example, a negative spin polarization. On the other hand, for example, the first magnetic layer 21 has a positive spin polarization.

[0025] As shown in Fig. 1(b), a current i c is supplied to the laminate 20. The current i c is supplied, for example, from the electric circuit 20D described above. As shown in Fig. 1(b), the current i c is oriented from the first magnetic layer 21 to the second magnetic layer 22. As shown in Fig. 1(b), an electron flow je accompanying the current i c is oriented from the second magnetic layer 22 to the first magnetic layer 21.

[0026] For example, when a current i c equal to or greater than a threshold flows through the stack 20, the magnetization of the magnetic layers included in the stack 20 oscillates. The stack 20 functions as, for example, a spin-torque oscillator (STO). As the current oscillates, an AC magnetic field (for example, a high-frequency magnetic field) is generated from the stack 20. The AC magnetic field generated by the stack 20 is applied to the magnetic recording medium 80, assisting writing to the magnetic recording medium 80. For example, microwave assisted magnetic recording (MAMR) can be implemented.

[0027] In the magnetic head 110, the first magnetic layer 21 and the second magnetic layer 22 function as, for example, an oscillation layer. For example, a negative transmitted spin torque from the second magnetic layer 22 acts on the first magnetic layer 21. For example, a spin torque reflected by the first magnetic layer 21 acts on the second magnetic layer 22. For example, the magnetization of the first magnetic layer 21 and the magnetization of the second magnetic layer 22 rotate while interacting with each other.

[0028] As shown in FIG. 1(b), the thickness of the first magnetic layer 21 along the first direction (the direction from the first magnetic pole 31 to the second magnetic pole 32) is defined as a first thickness t1. The thickness of the second magnetic layer 22 along the first direction is defined as a second thickness t2. In the first embodiment, for example, the first thickness t1 may be the same as the second thickness t2. This makes it easier to obtain oscillation, as will be described later.

[0029] The thickness of the first non-magnetic layer 41 along the first direction is defined as thickness t41. The thickness of the second non-magnetic layer 42 along the first direction is defined as thickness t42. The thickness of the third non-magnetic layer 43 along the first direction is defined as thickness t43. These thicknesses are, for example, 0.5 nm or more and 6 nm or less. When these thicknesses are 0.5 nm or more, stable oscillation becomes easy. When these thicknesses are 6 nm or less, for example, the spin transmittance is easily increased. For example, high oscillation intensity is easily obtained.

[0030] An example of a simulation result regarding the oscillation behavior in the laminate 20 will be described below. In the simulation model, a configuration shown in FIG. 1(b) is provided. That is, a first magnetic pole 31, a second magnetic pole 32, a first magnetic layer 21, a second magnetic layer 22, and first to third non-magnetic layers 41 to 43 are provided. The oscillation characteristics of magnetization when a current ic (current equal to or greater than a threshold value) illustrated in FIG. 1(b) is supplied is simulated. In the simulation model, the physical property values ​​of the first magnetic layer 21 are Fe 70 Co 30 The physical properties of the alloy are used. 70 Cr 30 The physical property values ​​of the alloy are used. The physical property values ​​of Cu are used as the physical property values ​​of the first non-magnetic layer 41 and the third non-magnetic layer 43. The physical property value of Ta is used as the physical property value of the second non-magnetic layer 42. The thicknesses t41 to t43 are 2 nm.

[0031] FIG. 3 is a graph illustrating the characteristics of the magnetic head. In the simulation illustrated in FIG. 3, the ratio of the first thickness t1 to the second thickness t2 is changed while the sum of the first thickness t1 of the first magnetic layer 21 and the second thickness t2 of the second magnetic layer 22 is kept constant at 19 nm. The horizontal axis of FIG. 3 is the thickness ratio RR1. The thickness ratio RR1 is the ratio of the first thickness t1 to the second thickness t2 (i.e., t1 / t2). The vertical axis is the oscillation strength OS. The oscillation strength OS is the sum of the product of the amplitude of the oscillation of the magnetization of the first magnetic layer 21 and the first thickness t1 and the product of the amplitude of the oscillation of the magnetization of the second magnetic layer 22 and the second thickness t2. When the oscillation strength OS is high, for example, the recording density by MAMR is likely to be improved.

[0032] As shown in FIG. 3, when the thickness ratio RR1 is close to 1, a high oscillation intensity OS is obtained. For example, when the thickness ratio RR1 is 0.25 or more and 4 or less, stable oscillation is obtained. The thickness ratio RR1 may be 0.33 or more. A higher oscillation intensity OS is obtained. The thickness ratio RR1 may be 3 or less. A higher oscillation intensity OS is obtained.

[0033] In the first embodiment, the first thickness t1 is preferably 0.25 to 4 times the second thickness t2. This provides a high oscillation intensity OS. Stable oscillation is obtained. The first thickness t1 may be 0.33 to 3 times the second thickness t2. A higher oscillation intensity OS is obtained. A more stable oscillation is obtained. According to the first embodiment, stable MAMR can be implemented. A magnetic head capable of improving recording density can be provided.

[0034] 4(a) and 4(b) are graphs illustrating the characteristics of the magnetic head. The horizontal axis of FIG. 4(a) is the first thickness t1. In FIG. 4(a), the second thickness t2 is 15 nm. The horizontal axis of FIG. 4(b) is the second thickness t2. In FIG. 4(b), the first thickness t1 is 15 nm. In FIG. 4(a) and FIG. 4(b), the current i c supplied to the stack 20 is 2.5×10 8 A / cm 2 The vertical axis in FIG. 4(a) and FIG. 4(b) is the oscillation intensity OS.

[0035] As shown in FIG. 4(a), the first thickness t1 is preferably 5 nm or more. This allows a high oscillation intensity OS to be obtained. The first thickness t1 may be, for example, 20 nm or less. For example, the distance (for example, the recording gap) between the first magnetic pole 31 and the second magnetic pole 32 can be shortened. For example, a high recording density can be easily obtained.

[0036] As shown in FIG. 4(b), the second thickness t2 is preferably 5 nm or more. This allows a high oscillation intensity OS to be obtained. The second thickness t2 may be 20 nm or less. For example, the recording gap can be shortened. For example, a high recording density can be easily obtained.

[0037] FIG. 5 is a graph illustrating the characteristics of the magnetic head. 5, the horizontal axis represents the sum ts of the first thickness t1 and the second thickness t2, and the vertical axis represents the oscillation intensity OS.

[0038] As shown in FIG. 5, the sum ts of the first thickness t1 and the second thickness t2 is preferably 15 nm or more. This allows a high oscillation intensity OS to be obtained. The sum ts may be 40 nm or less. For example, the recording gap can be shortened. For example, a high recording density can be easily obtained.

[0039] 6A and 6B are schematic plan views illustrating the magnetic head according to the first embodiment. 6(a), the magnetic head 111 according to the first embodiment includes a first magnetic pole 31, a second magnetic pole 32, and a laminate 20. In the magnetic head 111, the laminate 20 also includes a first magnetic layer 21, a second magnetic layer 22, a first non-magnetic layer 41, a second non-magnetic layer 42, and a third non-magnetic layer 43. In the magnetic head 111, at least one of the first magnetic layer 21 and the second magnetic layer 22 includes a plurality of regions. Other configurations of the magnetic head 111 may be similar to those of the magnetic head 110.

[0040] For example, the first magnetic layer 21 includes a first magnetic region 21a and a second magnetic region 21b. The second magnetic region 21b is between the first magnetic region 21a and the first non-magnetic layer 41. For example, the saturation magnetization of the first magnetic region 21a is larger than the saturation magnetization of the second magnetic region 21b. This makes it easier to obtain stable oscillation, for example.

[0041] For example, the saturation magnetization of the first magnetic region 21a is 1.2 times or more that of the second magnetic region 21b. This makes it easier to obtain stable oscillation. The saturation magnetization of the first magnetic region 21a may be 3 times or less that of the second magnetic region 21b. This makes it easier to obtain stable oscillation.

[0042] For example, the concentration of Fe in the first magnetic region 21a is higher than the concentration of Fe in the second magnetic region 21b. For example, the saturation magnetization of the first magnetic region 21a is likely to be greater than the saturation magnetization of the second magnetic region 21b. For example, the concentration of Ni in the first magnetic region 21a is lower than the concentration of Ni in the second magnetic region 21b. As a result, for example, the saturation magnetization of the first magnetic region 21a is likely to be greater than the saturation magnetization of the second magnetic region 21b. The boundary between the first magnetic region 21a and the second magnetic region 21b may be clear or unclear.

[0043] For example, the second magnetic layer 22 includes a third magnetic region 22c and a fourth magnetic region 22d. The fourth magnetic region 22d is between the third magnetic region 22c and the first non-magnetic layer 41. For example, the saturation magnetization of the third magnetic region 22c is larger than the saturation magnetization of the fourth magnetic region 22d. This makes it easier to obtain stable oscillation, for example.

[0044] For example, the saturation magnetization of the third magnetic region 22c is 1.2 times or more that of the fourth magnetic region 22d. This makes it easier to obtain stable oscillation. The saturation magnetization of the third magnetic region 22c may be 3 times or less that of the fourth magnetic region 22d. This makes it easier to obtain stable oscillation.

[0045] For example, the Fe concentration in the third magnetic region 22c is higher than the Fe concentration in the fourth magnetic region 22d. As a result, for example, the saturation magnetization of the third magnetic region 22c is likely to be greater than that of the fourth magnetic region 22d. For example, the concentration of the second element in the third magnetic region 22c is lower than that of the fourth magnetic region 22d. As a result, for example, the saturation magnetization of the third magnetic region 22c is likely to be greater than that of the fourth magnetic region 22d. The boundary between the third magnetic region 22c and the fourth magnetic region 22d may be clear or unclear.

[0046] 6(b), the magnetic head 112 according to the first embodiment includes a first magnetic pole 31, a second magnetic pole 32, and a laminate 20. In the magnetic head 112, the laminate 20 includes a third magnetic layer 23 in addition to a first magnetic layer 21, a second magnetic layer 22, a first non-magnetic layer 41, a second non-magnetic layer 42, and a third non-magnetic layer 43. Other configurations of the magnetic head 112 may be similar to those of the magnetic head 110 or the magnetic head 111.

[0047] The third magnetic layer 23 is provided between the second magnetic layer 22 and the second non-magnetic layer 42. The third magnetic layer 23 includes a first element including at least one of Fe, Co, and Ni. The third magnetic layer 23 does not include a second element. Alternatively, the concentration of the second element in the third magnetic layer 23 is lower than the concentration of the second element in the second magnetic layer 22. As already described, the second element includes at least one selected from the group consisting of Cr, V, Mn, Ti, and Sc.

[0048] For example, the saturation magnetization of the third magnetic layer 23 is higher than that of the second magnetic layer 22. This makes it easier to obtain stable oscillation, for example. The boundary between the third magnetic layer 23 and the first magnetic layer 21 may be clear or unclear. The third magnetic layer 23 may be continuous with the second magnetic layer 22.

[0049] In the magnetic head 112, the first thickness t1 of the first magnetic layer 21 is, for example, 0.8 to 1.25 times the sum of the third thickness t3 of the third magnetic layer 23 and the second thickness t2 of the second magnetic layer 22 along the first direction (the direction from the first magnetic pole 31 to the second magnetic pole 32). For example, a high oscillation intensity OS is obtained. Stable oscillation is obtained.

[0050] 7A and 7B are schematic views illustrating the characteristics of the magnetic head according to the first embodiment. 7(a) and 7(b) are plots of the horizontal axis representing the write current Iw flowing through the coil 30c. The write magnetic field generated by at least one of the first magnetic pole 31 and the second magnetic pole 32 changes in response to the write current Iw flowing through the coil 30c. The write magnetic field is applied to the laminate 20. Thus, the horizontal axis represents the magnetic field applied to the laminate 20. The vertical axis represents the electrical resistance Rx of the laminate 20.

[0051] In Fig. 7(a), the current i c supplied to the laminate 20 is smaller than the threshold current I th of oscillation. In the example of Fig. 7(a), the current i c is, for example, 1.0 × 10 6 A / cm 2 In FIG. 7B, the current i c supplied to the laminate 20 is greater than the threshold current I th. In the example of FIG. 7B, the current i c is 1.0×10 8 A / cm 2 7(b) is 100 times the current ic in FIG. 7(a). FIG. 7(a) corresponds to the characteristics in a non-oscillating state. FIG. 7(b) corresponds to the characteristics in an oscillating state. These figures illustrate the characteristics of the average value of the electrical resistance Rx over time. When the laminate 20 is oscillating, the electrical resistance Rx changes with the oscillation. The time-averaged resistance is used as the electrical resistance Rx. The time-averaged resistance can also suppress the effects of noise, for example.

[0052] As shown in FIG. 7(a), when the current ic is sufficiently smaller than the threshold current Ith, the electrical resistance Rx increases as the absolute value of the recording current Iw (i.e., the magnetic field) increases. When the absolute value of the recording current Iw is sufficiently large, the electrical resistance Rx saturates. For example, the recording current Iw when the electrical resistance Rx saturates is 50 mA. The magnetic field at this time is about 15,000 Oe.

[0053] In the magnetic recording device head according to the first embodiment, for example, the characteristic illustrated in FIG. 7(a) occurs. As shown in FIG. 7(a), the electrical resistance Rx of the laminate 20 is a first resistance Rx1 when the recording current Iw is a first current I1. The electrical resistance Rx is a second resistance Rx2 when the recording current Iw is a second current I2. The electrical resistance Rx is a third resistance Rx3 when the recording current Iw is a third current I3. The absolute value of the first current I1 is smaller than the absolute value of the second current I2 and smaller than the absolute value of the third current I3. The direction of the second current I2 is opposite to the direction of the third current I3. The first resistance Rx1 is lower than the second resistance Rx2 and lower than the third resistance Rx3. For example, a valley-type current-resistance characteristic occurs. The first current I1 may be substantially zero.

[0054] As shown in FIG. 7(b), when the current ic is larger than the threshold current Ith and oscillation occurs, the electrical resistance Rx shows a crest and valley characteristic. In this case, too, when the absolute values ​​of the second current I2 and the third current I3 are sufficiently large, it can be considered as a valley-type characteristic. For example, the absolute values ​​of the second current I2 and the third current I3 may be values ​​at which the electrical resistance Rx is saturated when the current ic is sufficiently smaller than the threshold current Ith. In this case, too, the first resistance Rx1 is lower than the second resistance Rx2 and lower than the third resistance Rx3. In contrast, in a general STO, a crest-type characteristic occurs. The valley-type characteristic in the first embodiment is considered to be a unique characteristic due to the configuration in the first embodiment.

[0055] Such a unique characteristic may be related to the fact that the first magnetic layer 21 has a positive polarization and the second magnetic layer 22 has a negative polarization. In such a combination, when the absolute value of the recording current Iw is large (i.e., when the absolute value of the magnetic field is large), it is considered that the magnetization directions of the first magnetic layer 21 and the second magnetic layer 22 become closer to being parallel to each other, and the resistance increases. In general STO, both magnetic layers have a positive polarization. When the magnetization directions become closer to being parallel to each other, the resistance decreases.

[0056] FIG. 8 is a schematic view illustrating the characteristics of the magnetic head according to the first embodiment. The horizontal axis of Fig. 8 is time tm. The vertical axis is magnetization Mz (normalized value). Fig. 8 shows an example of magnetization Mz1 of the first magnetic layer 21 and magnetization Mz2 of the second magnetic layer 22. As shown in Fig. 8, magnetization Mz1 and magnetization Mz2 rotate in opposite phases (for example, while maintaining opposite directions).

[0057] The first embodiment may include the following configurations (for example, technical solutions). (Configuration 1) A first magnetic pole; A second magnetic pole; a laminate provided between the first magnetic pole and the second magnetic pole; Equipped with The laminate comprises: A first magnetic layer; a second magnetic layer provided between the first magnetic layer and the second magnetic pole; a first nonmagnetic layer provided between the first magnetic layer and the second magnetic layer; a second nonmagnetic layer provided between the second magnetic layer and the second magnetic pole; a third nonmagnetic layer provided between the first magnetic pole and the first magnetic layer; Including, the first magnetic layer includes a first element including at least one of Fe, Co, and Ni; the second magnetic layer includes the first element and a second element including at least one selected from the group consisting of Cr, V, Mn, Ti, and Sc; the first magnetic layer does not contain the second element, or the concentration of the second element in the first magnetic layer is lower than the concentration of the second element in the second magnetic layer; A magnetic head, wherein a first thickness of the first magnetic layer along a first direction from the first magnetic pole to the second magnetic pole is between 0.25 and 4 times a second thickness of the second magnetic layer along the first direction.

[0058] (Configuration 2) 2. The magnetic head of configuration 1, wherein the first thickness is greater than or equal to 0.33 times the second thickness.

[0059] (Configuration 3) 3. The magnetic head according to claim 1, wherein the third nonmagnetic layer is in contact with the first magnetic pole and the first magnetic layer.

[0060] (Configuration 4) 4. The magnetic head according to any one of configurations 1 to 3, wherein the first nonmagnetic layer is in contact with the first magnetic layer and the second magnetic layer.

[0061] (Configuration 5) 5. The magnetic head according to any one of configurations 1 to 4, wherein the second nonmagnetic layer is in contact with the second magnetic layer and the second magnetic pole.

[0062] (Configuration 6) 2. The magnetic head of claim 1, wherein at least one of the first nonmagnetic layer, the second nonmagnetic layer, and the third nonmagnetic layer contains a third element including at least one selected from the group consisting of Cu, Au, Cu, V, Al, and Ag.

[0063] (Configuration 7) 7. The magnetic head according to any one of configurations 1 to 6, wherein the second thickness is 5 nm or more.

[0064] (Configuration 8) The magnetic head according to any one of configurations 1 to 7, wherein the first thickness is 5 nm or more.

[0065] (Configuration 9) 9. The magnetic head according to any one of configurations 1 to 8, wherein the sum of the first thickness and the second thickness is 15 nm or more.

[0066] (Configuration 10) the first magnetic layer includes a first magnetic region and a second magnetic region, the second magnetic region is between the first magnetic region and the first nonmagnetic layer, 10. The magnetic head according to any one of configurations 1 to 9, wherein the saturation magnetization of the first magnetic region is greater than the saturation magnetization of the second magnetic region.

[0067] (Configuration 11) the first magnetic layer includes a first magnetic region and a second magnetic region, the second magnetic region is between the first magnetic region and the first nonmagnetic layer, 10. The magnetic head according to any one of configurations 1 to 9, wherein the concentration of Fe in the first magnetic region is higher than the concentration of Fe in the second magnetic region.

[0068] (Configuration 12) the second magnetic layer includes a third magnetic region and a fourth magnetic region, the fourth magnetic region is between the third magnetic region and the first nonmagnetic layer, 12. The magnetic head according to any one of configurations 1 to 11, wherein the saturation magnetization of the third magnetic region is greater than the saturation magnetization of the fourth magnetic region.

[0069] (Configuration 13) the second magnetic layer includes a third magnetic region and a fourth magnetic region, the fourth magnetic region is between the third magnetic region and the first nonmagnetic layer, 13. The magnetic head according to any one of configurations 1 to 12, wherein the Fe concentration in the third magnetic region is higher than the Fe concentration in the fourth magnetic region.

[0070] (Configuration 14) The stack further includes a third magnetic layer, the third magnetic layer is provided between the second magnetic layer and the second nonmagnetic layer, the third magnetic layer includes a first element including at least one of Fe, Co, and Ni; A magnetic head described in any one of configurations 1 to 13, wherein the third magnetic layer does not contain the second element, or the concentration of the second element in the third magnetic layer is lower than the concentration of the second element in the second magnetic layer.

[0071] (Configuration 15) 15. The magnetic head according to any one of configurations 1 to 14, wherein the concentration of the second element in the second magnetic layer is 10 atomic % or more and 80 atomic % or less.

[0072] (Configuration 16) 16. The magnetic head according to any one of configurations 1 to 15, wherein a current is supplied to the stack in a direction from the first magnetic layer to the second magnetic layer.

[0073] (Configuration 17) 17. The magnetic head of claim 16, wherein an AC magnetic field is generated from the stack when the current is supplied to the stack.

[0074] (Configuration 18) Further comprising a coil; a recording magnetic field generated from at least one of the first magnetic pole and the second magnetic pole changes in response to a recording current flowing through the coil; an electrical resistance of the stack is a first resistance when the recording current is a first current; the electrical resistance is a second resistance when the recording current is a second current, the electrical resistance is a third resistance when the recording current is a third current, an absolute value of the first current is smaller than an absolute value of the second current and smaller than an absolute value of the third current; a direction of the second current is opposite to a direction of the third current; 18. The magnetic head according to any one of configurations 1 to 17, wherein the first resistance is lower than the second resistance and lower than the third resistance.

[0075] (Configuration 19) A magnetic head according to any one of configurations 1 to 16, An electric circuit; Equipped with The electric circuit is capable of supplying an electric current to the laminate; The current has a direction from the first magnetic layer to the second magnetic layer.

[0076] (Configuration 20) When the electric circuit supplies a current to the laminate, 20. The magnetic recording device according to claim 19, wherein an AC magnetic field is generated from the laminate.

[0077] In the first embodiment, the second magnetic layer 2 2 is (Fe 100-x Co x ) 100-y E y (10 atm%≦x≦50 atm%, 10 atm%≦y≦90 atm%). The second element E includes at least one selected from the group consisting of Cr, V, Mn, Ti, and Sc. The composition ratio x and the composition ratio y are in atomic percent (atm%). 1 does not contain the second element E. Alternatively, the concentration of the second element E in the first magnetic layer 21 is lower than the concentration of the second element E in the second magnetic layer 22. With such a material, it is easy to obtain, for example, a high saturation magnetic flux density and a negative spin polarization with a large absolute value in the second magnetic layer 22.

[0078] 9(a) and 9(b) are graphs illustrating the characteristics of the magnetic layer included in the magnetic head. FIG. 9(a) illustrates the properties when the magnetic layer does not contain the second element. In this example, the magnetic layer contains Fe 100-x Co x The horizontal axis of FIG. 9(a) is the composition ratio x (Co concentration), and the vertical axis is the saturation magnetic flux density Bm1. As shown in FIG. 9(a), a tm% or more 50atm% belowA high saturation magnetic flux density Bm1 can be obtained. When the composition ratio x is 75 atm or less, the magnetic layer has a BCC structure. When the composition ratio x exceeds 75 atm, the magnetic layer has an fcc structure.

[0079] FIG. 9(b) illustrates the characteristics when the composition ratio of the second element in the magnetic layer is changed. The horizontal axis of FIG. 9(b) is the composition ratio y. In this example, the second element E is Cr. The vertical axis is the saturation magnetic flux density Bm1. As shown in FIG. 9(b), when the composition ratio y is high, the saturation magnetic flux density Bm1 is obtained. When the magnetic layer is Fe 50 Co 50 , or Fe 90 Co 10 When the magnetic layer contains Fe, substantially the same characteristics are obtained. 70 Co 30 When the magnetic layer contains the second element, a higher saturation magnetic flux density Bm1 can be obtained at the same composition ratio y compared to other compositions. When the magnetic layer contains the second element, the composition ratio x is preferably 10 atm % or more and 50 atm % or less.

[0080] FIG. 10 is a graph illustrating the characteristics of the magnetic layer included in the magnetic head. FIG. 10 illustrates the change in spin polarization of the magnetic layer when the composition ratio y is changed when the composition ratio of Co to Fe is fixed. The horizontal axis of FIG. 10 is the composition ratio y of the second element E. The vertical axis is the spin polarization Ps1 (spin polarization value). As shown in FIG. 10, when the composition ratio y of the second element E is 3 atm% or more, a negative spin polarization Ps1 is obtained. When the composition ratio y is high, the absolute value of the negative spin polarization Ps1 becomes large. When the composition ratio y is 10% or more, a negative spin polarization Ps1 with a large absolute value is obtained. For example, the composition ratio y may be 10 atm% or more and 30 atm% or less.

[0081] As can be seen from Fig. 9(b) and Fig. 10, in the embodiment, the composition ratio x of Co is 10 atm% or more and 50 atm% or less, and the composition ratio y of the second element E is preferably 10 atm% or more. The composition ratio y of the second element E is preferably 90 atm% or less. This allows a high saturation magnetic flux density Bm1 to be obtained. In the embodiment, the composition ratio y of the second element E may be 10 atm% or more and 50 atm% or less.

[0082] FIG. 11 is a graph illustrating the characteristics of the magnetic layer included in the magnetic head. FIG. 11 illustrates the oscillation strength OS when the composition of the second magnetic layer 22 is changed. In this example, the composition ratio y is 20 atm%, and the composition ratio x of Co is changed. The second element E is Cr. The horizontal axis of FIG. 11 is the composition ratio x. The vertical axis is the oscillation strength OS. As can be seen from FIG. 11, a high oscillation strength OS can be obtained when the composition ratio x is 10 atm% or more and 50 atm% or less. Under these conditions, for example, the recording density by MAMR is likely to be improved. It is more preferable that the composition ratio x is 25 atm% or more and 35 atm% or less. A high oscillation strength OS can be easily obtained stably.

[0083] In this way, it is preferable that the second magnetic layer 22 (for example, a magnetic layer having a negative spin polarization) has the above composition. This makes it easier to obtain, for example, a high saturation magnetic flux density Bm1 and a negative spin polarization Ps1 with a large absolute value. For example, it is easier to obtain stable oscillation.

[0084] In the first embodiment, the second thickness t2 of the second magnetic layer 22 is preferably 5 nm or more and 15 nm or less. In the first embodiment, the thickness t41 of the first non-magnetic layer 41 and the thickness t42 of the second non-magnetic layer 42 are preferably 0.5 nm or more and 6 nm or less.

[0085] Second embodiment FIG. 12 is a schematic cross-sectional view illustrating a portion of the magnetic recording device according to the second embodiment. The magnetic recording device 210 according to the second embodiment also includes a magnetic head 110A and an electric circuit 20D. The magnetic recording device 210 may include a magnetic recording medium 80. In the magnetic recording device 210, for example, at least a recording operation is performed. In the recording operation, information is recorded on the magnetic recording medium 80 using the magnetic head 110A.

[0086] In this example as well, the electric circuit 20D (see FIG. 2) is electrically connected to the laminate 20. In this example, the laminate 20 is electrically connected to the first magnetic pole 31 and the second magnetic pole 32. A first terminal T1 and a second terminal T2 are provided on the magnetic head 110A. The first terminal T1 is electrically connected to the laminate 20 via the first wiring W1 and the first magnetic pole 31. The second terminal T2 is electrically connected to the laminate 20 via the second wiring W2 and the second magnetic pole 32. For example, a current (for example, a direct current) is supplied to the laminate 20 from the electric circuit 20D.

[0087] 12, the stack 20 includes a first magnetic layer 21, a second magnetic layer 22, a third magnetic layer 23, a first non-magnetic layer 41, a second non-magnetic layer 42, and a third non-magnetic layer 43. In this example, a fourth non-magnetic layer 44 is provided.

[0088] The second magnetic layer 22 is provided between the first magnetic pole 31 and the first magnetic layer 21. The third magnetic layer 23 is provided between the first magnetic pole 31 and the second magnetic layer 22. The first non-magnetic layer 41 is provided between the first magnetic layer 21 and the second magnetic pole 32. The second non-magnetic layer 42 is provided between the second magnetic layer 22 and the first magnetic layer 21. The third non-magnetic layer 43 is provided between the third magnetic layer 23 and the second magnetic layer 22. In the case where the fourth non-magnetic layer 44 is provided, the fourth non-magnetic layer 44 is provided between the first magnetic pole 31 and the third magnetic layer 23.

[0089] The first magnetic layer 21 includes at least one of Fe, Co, and Ni. The second magnetic layer 22 includes at least one of Fe, Co, and Ni. For example, the first magnetic layer 21 and the second magnetic layer 22 have positive spin polarization.

[0090] The third magnetic layer 23 includes a first element and a second element. The first element includes at least one of Fe, Co, and Ni. The second element includes at least one selected from the group consisting of Cr, V, Mn, Ti, and Sc. The second element is, for example, an additive element. The ratio (for example, concentration) of the second element in the third magnetic layer 23 is, for example, not less than 1 atomic % and not more than 80 atomic %. For example, the third magnetic layer 23 has a negative spin polarization.

[0091] The first magnetic layer 21 and the second magnetic layer 22 are substantially free of the second element. Alternatively, the concentration of the second element in the first magnetic layer 21 and the second magnetic layer 22 is lower than the concentration of the second element in the third magnetic layer 23.

[0092] The first nonmagnetic layer 41 includes, for example, at least one selected from the group consisting of Cu, Ag, Au, Al, and Cr. The first nonmagnetic layer 41 functions as, for example, a layer that propagates polarized spins.

[0093] The second nonmagnetic layer 42 includes at least one selected from the group consisting of, for example, Ta, Pt, W, Mo, Ir, Ru, Tb, Rh, Cr, and Pd. The second nonmagnetic layer 42 functions as, for example, a layer that damps polarized spins.

[0094] The third nonmagnetic layer 43 includes at least one selected from the group consisting of Cu, Ag, Au, Al, and Cr. The third nonmagnetic layer 43 functions as, for example, a layer that propagates polarized spins.

[0095] The fourth nonmagnetic layer 44 includes at least one selected from the group consisting of Cu, Ag, Au, Al, and Cr. The fourth nonmagnetic layer 44 functions as, for example, a layer that propagates polarized spins.

[0096] 12, for example, a current jc1 supplied from the electric circuit 20D to the laminate 20 is oriented from the second magnetic pole 32 to the first magnetic pole 31. The current jc1 is oriented from the first magnetic layer 21 to the second magnetic layer 22. An electron current je1 is oriented from the first magnetic pole 31 to the second magnetic pole 32.

[0097] For example, when no current jc1 is supplied to the stack 20, the magnetization direction of the first magnetic layer 21 is substantially the same as the magnetization direction of the first magnetic pole 31 and the magnetization direction of the second magnetic pole 32. A part of the magnetic field (recording magnetic field) emitted from the first magnetic pole 31 is directed toward the magnetic recording medium 80. On the other hand, another part of the magnetic field (recording magnetic field) emitted from the first magnetic pole 31 passes through the stack 20 and enters the second magnetic pole 32 without being directed toward the magnetic recording medium 80. For this reason, the proportion of the recording magnetic field emitted from the first magnetic pole 31 directed toward the magnetic recording medium 80 is small.

[0098] When the current jc1 is supplied to the stack 20, the magnetization direction of the first magnetic layer 21 is reversed relative to the magnetization direction of the first magnetic pole 31 and the magnetization direction of the second magnetic pole 32. This makes it difficult for the magnetic field (recording magnetic field) emitted from the first magnetic pole 31 to be directed toward the stack 20. Therefore, the proportion of the recording magnetic field emitted from the first magnetic pole 31 that is directed toward the magnetic recording medium 80 becomes higher than when the current jc1 is not supplied to the stack 20. The recording magnetic field emitted from the first magnetic pole 31 is effectively applied to the magnetic recording medium 80.

[0099] This phenomenon becomes more pronounced as the distance (recording gap) between the first magnetic pole 31 and the second magnetic pole 32 becomes shorter. By using such a laminate 20, good recording can be performed even when the recording gap becomes small. According to the second embodiment, the recording gap that allows good recording can be made small. According to the second embodiment, it is possible to provide a magnetic recording device that can improve the recording density.

[0100] On the other hand, there is Microwave Assisted Magnetic Recording (MAMR), in which a high-frequency magnetic field generated from a laminate including multiple magnetic layers is applied to a magnetic recording medium 80 to locally control the magnetic properties of the magnetic recording medium 80 for recording. In MAMR, a high-frequency magnetic field is generated by oscillation of the magnetization of the magnetic layers.

[0101] In contrast, in the second embodiment, the magnetization of the first magnetic layer 21 is reversed with respect to the magnetization of the first magnetic pole 31 and the magnetization of the second magnetic pole 32. By an operation different from MAMR, the magnetic field generated from the first magnetic pole 31 is efficiently applied to the magnetic recording medium 80.

[0102] An example of the characteristics of the magnetic head 110A according to the second embodiment will now be described.

[0103] 13A and 13B are schematic views illustrating the characteristics of the magnetic recording device according to the embodiment. These figures show a schematic diagram of the relationship between the magnitude of the current jc1 flowing through the laminate 20 according to the embodiment and the electrical resistance of the laminate 20. The horizontal axis of these figures is the magnitude of the current jc1. The vertical axis of FIG. 13(a) is the electrical resistance Rz1 of the laminate 20.

[0104] As shown in Fig. 13(a), as the current jc1 increases, the electrical resistance Rz1 increases. As shown in Fig. 13(a), the magnitude of the current jc1 can be divided into a first current range ir1, a second current range ir2, and a third current range ir3. The third current range ir3 is between the first current range ir1 and the second current range ir2.

[0105] In the first current range ir1 and the second current range ir2, the electrical resistance Rz1 changes according to a quadratic function with respect to the magnitude of the current jc1, which is believed to be due to the fact that the temperature of the laminate 20 increases as the current jc1 increases.

[0106] The change in the electrical resistance Rz1 in the third current range ir3 is not influenced by an increase in temperature, and is considered to be due to the magnetoresistance effect based on the reversal rate of the magnetization of the magnetic layer.

[0107] FIG. 13(b) shows the relationship between the magnitude of the current jc1 and the electrical resistance Rz2, with the change in the quadratic function (the influence of temperature) in FIG. 13(a) removed. As shown in FIG. 13(b), when the influence of the quadratic function is removed, the electrical resistance Rz2 is substantially constant in the first current range ir1. Or, the electrical resistance Rz2 changes more slowly in the first current range ir1 than in the third current range ir3. The electrical resistance Rz2 changes in the third current range ir3. The electrical resistance Rz2 is substantially constant in the second current range ir2. Or, the electrical resistance Rz2 changes more slowly in the second current range ir2 than in the third current range ir3.

[0108] 13(b), when the current jc1 flowing through the laminate 20 is a first current i1, the electrical resistance Rz2 of the laminate 20 is a first resistance R1. The first current i1 is in a first current range ir1.

[0109] 13(b), when the current jc1 flowing through the laminate 20 is the second current i2, the electrical resistance Rz2 of the laminate 20 is the second resistance R2. The second current i2 is greater than the first current i1. The second current i2 is in a second current range ir2. The second resistance R2 is higher than the first resistance R1.

[0110] At a third current i3 between the first current i1 and the second current i2, the electrical resistance Rz2 of the laminate 20 is a third resistance R3. The third current i3 is in a third current range ir3.

[0111] For example, when the current jc1 is the first current i1 or the second current i2, the electrical resistance Rz2 does not substantially oscillate. For example, when the current jc1 is the third current i3, the electrical resistance Rz2 oscillates. The first current i1, the second current i2, and the third current i3 are oriented from the first magnetic layer 21 to the second magnetic layer 22.

[0112] 14(a) to 14(c) are schematic views illustrating the characteristics of the magnetic recording device according to the second embodiment. These figures show examples of signals obtained by performing FFT (Fast Fourier Transform) processing on a portion of the signal of the electrical resistance Rz2. The signal of the electrical resistance Rz2 includes a component that changes over time (high frequency component) and a component that does not change substantially over time (a component of the temporal average value). In the FFT processing, the component of the electrical resistance Rz2 that changes over time is processed. The horizontal axis of these figures is the frequency ff. The vertical axis is the signal intensity Int. FIG. 14(a) corresponds to the case where the current jc1 is the first current i1. FIG. 14(b) corresponds to the case where the current jc1 is the third current i3. FIG. 14(c) corresponds to the case where the current jc1 is the second current i2.

[0113] 14(b), when the current jc1 is the third current i3, a peak p1 is observed at a frequency fp1. This peak corresponds to the occurrence of high-frequency oscillation in the laminate 20.

[0114] 14(a) and 14(c), when the current jc1 is the first current i1 or the second current i2, the peak p1 is not clearly observed. At these currents, effective magnetization oscillation in the MAMR does not substantially occur.

[0115] In this manner, when the current jc1 flowing through the laminate 20 is the third current i3 between the first current i1 and the second current i2, the electrical resistance Rz2 of the laminate 20 oscillates.

[0116] In the second embodiment, a recording operation is performed using the stack 20 having such characteristics.

[0117] In the second embodiment, in a recording operation in which information is recorded on the magnetic recording medium 80 using the magnetic head 110A, the electric circuit 20D can supply the above-mentioned second current i2 to the stack 20. By performing a recording operation in which the recording circuit 30D supplies the recording current Iw to the coil while supplying the above-mentioned second current i2, it is possible to increase the amount of the recording magnetic field directed from the first magnetic pole 31 to the magnetic recording medium 80, compared to a case in which the recording operation is performed without supplying the second current i2. It is possible to reduce the recording gap that allows good recording. According to the embodiment, it is possible to provide a magnetic recording device that allows for improved recording density.

[0118] An example of the characteristics of a magnetic recording device will now be described. FIG. 15 is a schematic diagram illustrating the characteristics of a magnetic recording device. 15 illustrates simulation results of the characteristics of the magnetic head including the stack 20 under the first condition CH1, the second condition CH2, and the third condition CH3. Under the first condition CH1, the configuration of the magnetic head 110A described above is applied. That is, the second nonmagnetic layer 42 is Ta, and the second nonmagnetic layer 42 attenuates, for example, polarized spins.

[0119] Under the second condition CH2, the second nonmagnetic layer 42 is made of Cu, and the second nonmagnetic layer 42 propagates, for example, polarized spins. Other configurations under the second condition CH2 are similar to those under the first condition CH1.

[0120] In the third condition CH3, the second nonmagnetic layer 42 is not provided, and the first magnetic layer 21 and the second magnetic layer 22 are in contact with each other. Other configurations in the third condition CH3 are similar to the configurations in the first condition CH1.

[0121] The horizontal axis of Fig. 15 is time tm. At a first time tm1, the polarity of the recording current Iw is reversed. The vertical axis of Fig. 15 is a parameter P1 corresponding to the amount of magnetization reversal. In the first condition CH1, the second condition CH2, and the third condition CH3, the parameter P1 corresponds to the amount of magnetization reversal between the first magnetic pole 31 and the second magnetic pole 32.

[0122] 15 also illustrates the characteristic PM of the magnetization direction of the first magnetic pole 31. With respect to the characteristic PM, a parameter P1 corresponds to the magnetization direction of the first magnetic pole 31. In the example of FIG. 15, the polarity of the recording current Iw is reversed at a first time tm1 (when the time tm is 0.60 ns). When the time tm is 0.62 ns, the magnetization direction of the first magnetic pole 31 starts to change. When the time tm is 0.67 ns, the change in the magnetization direction of the first magnetic pole 31 essentially ends.

[0123] 15, under the second condition CH2, the absolute value of the parameter P1 is small. Under the second condition CH2, the magnetization existing between the first magnetic pole 31 and the second magnetic pole 32 is not clearly reversed with respect to the magnetization of the first magnetic pole 31.

[0124] As shown in FIG. 15, it can be seen that under the first condition CH1 and the third condition CH3, the magnetization existing between the first magnetic pole 31 and the second magnetic pole 32 is substantially reversed with respect to the magnetization of the first magnetic pole 31. The parameter P1 under the first condition CH1 changes faster than the parameter P1 under the third condition CH3. Under the first condition CH1, high-speed magnetization reversal is obtained. Under the first condition CH1, the magnetization of the first magnetic layer 21 changes quickly, so that high follow-up to the change in the magnetization of the first magnetic pole 31 is obtained. Under the first condition CH1, for example, under practical use conditions, the BER (Bit Error Rate) can be effectively reduced.

[0125] In the second embodiment, the BER can be effectively reduced, and the write gap that enables good recording can be made smaller. According to the second embodiment, a magnetic recording device that allows for improved recording density can be provided.

[0126] In the second embodiment, high recording performance can be obtained during high-speed recording operations at high frequencies, and recording density can be improved more effectively.

[0127] FIG. 16 is a schematic cross-sectional view illustrating a portion of the magnetic recording device according to the second embodiment. FIG. 16 illustrates a magnetic head 110A.

[0128] As shown in FIG. 16, the first magnetic layer 21 has a thickness t21. The second magnetic layer 22 has a thickness t22. The third magnetic layer 23 has a thickness t23. The first non-magnetic layer 41 has a thickness t41. The second non-magnetic layer 42 has a thickness t42. The third non-magnetic layer 43 has a thickness t43. The fourth non-magnetic layer 44 has a thickness t44. These thicknesses are lengths along the first direction D1. As already explained, the first direction D1 may be inclined with respect to the X-axis direction.

[0129] In the magnetic head 110A, the thickness t21 of the first magnetic layer 21 is, for example, 2 nm or more and 10 nm or less. When the thickness t21 is 2 nm or more, for example, the magnetic field toward the magnetic recording medium 80 can be effectively increased. When the thickness t21 is 8 nm or less, for example, efficient magnetization reversal can be easily obtained.

[0130] In the magnetic head 110A, the thickness t22 of the second magnetic layer 22 is, for example, 2 nm or more and 4 nm or less. If the thickness t22 is 2 nm or more, it is easy to obtain a higher gain during high-speed operation. If the thickness t22 is 4 nm or less, it is easy to obtain stable operation.

[0131] In the magnetic head 110A, the thickness t23 of the third magnetic layer 23 is, for example, 2 nm or more and 5 nm or less. When the thickness t23 is 2 nm or more, for example, electrons passing through the third magnetic layer 23 are more likely to spin. When the thickness t23 is 5 nm or less, for example, the magnetization of the third magnetic layer 23 is more likely to be stable.

[0132] In the magnetic head 110A, the thickness t41 of the first nonmagnetic layer 41 is, for example, not less than 1 nm and not more than 5 nm. When the thickness t41 is in this range, for example, electrons spin-polarized by the second magnetic pole 32 can easily reach the first magnetic layer 21.

[0133] In the magnetic head 110A, the thickness t42 of the second nonmagnetic layer 42 is, for example, not less than 1 nm and not more than 5 nm. When the thickness t42 is in this range, for example, a higher gain can be easily obtained.

[0134] In the magnetic head 110A, the thickness t43 of the third nonmagnetic layer 43 is, for example, not less than 1 nm and not more than 5 nm. When the thickness t43 is in this range, for example, the magnetization of the second magnetic layer 22 and the magnetization of the third magnetic layer 23 are easily stabilized relative to each other.

[0135] In the magnetic head 110A, the thickness t44 of the fourth nonmagnetic layer 44 is, for example, not less than 1 nm and not more than 5 nm. When the thickness t44 is in this range, for example, the magnetization of the third magnetic layer 23 becomes more stable.

[0136] In the second embodiment, for example, the first nonmagnetic layer 41 contacts the first magnetic layer 21 and the second magnetic pole 32. For example, the second nonmagnetic layer 42 contacts the second magnetic layer 22 and the first magnetic layer 21. For example, the third nonmagnetic layer 43 contacts the third magnetic layer 23 and the second magnetic layer 22. For example, the fourth nonmagnetic layer 44 contacts the first magnetic pole 31 and the third magnetic layer 23.

[0137] FIG. 17 is a schematic cross-sectional view illustrating a portion of the magnetic recording device according to the second embodiment. 17, the magnetic head 111A according to the second embodiment does not include the fourth nonmagnetic layer 44. In the magnetic head 111A, the first magnetic pole 31 is in contact with the third magnetic layer 23. Other configurations of the magnetic head 111A may be similar to those of the magnetic head 110A.

[0138] The magnetic head 111A also achieves high speed magnetization reversal. The BER can be effectively reduced, and the recording gap for good recording can be made smaller. According to the second embodiment, a magnetic recording device capable of improving recording density can be provided.

[0139] In the magnetic head 110A and the magnetic head 111A, the third nonmagnetic layer 43 preferably contains Cr, which makes it easier to stabilize the magnetization of the second magnetic layer 22, for example.

[0140] Third embodiment An example of the third embodiment will be described below. In the following description, descriptions of parts similar to those of the first embodiment will be omitted as appropriate.

[0141] FIG. 18 is a schematic cross-sectional view illustrating a portion of the magnetic recording device according to the third embodiment. As shown in FIG. 18, the magnetic recording device 210 according to the third embodiment includes a magnetic head 120A, a magnetic recording medium 80, and an electric circuit 20D. In the magnetic head 120A, the laminate 20 also includes a first magnetic layer 21, a second magnetic layer 22, a third magnetic layer 23, a first non-magnetic layer 41, a second non-magnetic layer 42, and a third non-magnetic layer 43. In this example, a fourth non-magnetic layer 44 is provided. In the magnetic head 120A, the second magnetic layer 22 is also provided between the first magnetic pole 31 and the first magnetic layer 21. The third magnetic layer 23 is provided between the first magnetic pole 31 and the second magnetic layer 22. The first non-magnetic layer 41 is provided between the first magnetic layer 21 and the second magnetic pole 32. The second non-magnetic layer 42 is provided between the second magnetic layer 22 and the first magnetic layer 21. The third nonmagnetic layer 43 is provided between the third magnetic layer 23 and the second magnetic layer 22. When the fourth nonmagnetic layer 44 is provided, the fourth nonmagnetic layer 44 is provided between the first magnetic pole 31 and the third magnetic layer 23.

[0142] In the magnetic head 120A, the first magnetic layer 21 includes a first element including at least one of Fe, Co, and Ni, and a second element including at least one selected from the group consisting of Cr, V, Mn, Ti, and Sc. The first magnetic layer 21 has, for example, a negative polarization. The concentration of the second element in the first magnetic layer 21 is, for example, 1 atomic % or more and 80 atomic % or less.

[0143] In the magnetic head 120A, the second magnetic layer 22 includes at least one of Fe, Co, and Ni. The second magnetic layer 22 does not substantially include the second element. Alternatively, the concentration of the second element in the second magnetic layer 22 is lower than the concentration of the second element in the first magnetic layer 21. The second magnetic layer 22 has, for example, a positive polarization.

[0144] In the magnetic head 120A, the third magnetic layer 23 includes a third element including at least one of Fe, Co, and Ni, and a fourth element including at least one selected from the group consisting of Cr, V, Mn, Ti, and Sc. The third magnetic layer 23 has, for example, negative polarization. The concentration of the fourth element in the third magnetic layer 23 is, for example, 1 atomic % or more and 80 atomic % or less. The second magnetic layer 22 does not substantially include the fourth element. Alternatively, the concentration of the fourth element in the second magnetic layer 22 is lower than the concentration of the fourth element in the third magnetic layer 23.

[0145] In the magnetic head 120A, for example, the first nonmagnetic layer 41 includes at least one selected from the group consisting of Cu, Ag, Au, Al, and Cr. In the magnetic head 120A, the first nonmagnetic layer 41 functions as, for example, a layer that propagates polarized spins.

[0146] In the magnetic head 120A, for example, the second nonmagnetic layer 42 includes at least one selected from the group consisting of Cu, Ag, Au, Al, and Cr. In the magnetic head 120A, the second nonmagnetic layer 42 functions as, for example, a layer that propagates polarized spins.

[0147] In the magnetic head 120A, for example, the third nonmagnetic layer 43 includes at least one selected from the group consisting of Cu, Ag, Au, Al, and Cr. In the magnetic head 120A, the third nonmagnetic layer 43 functions as, for example, a layer that propagates polarized spins.

[0148] In the magnetic head 120A, a fourth non-magnetic layer 44 may be provided between the first magnetic pole 31 and the third magnetic layer 23. The fourth non-magnetic layer 44 includes, for example, at least one selected from the group consisting of Cu, Ag, Au, Al, and Cr. In the magnetic head 120A, the fourth non-magnetic layer 44 functions, for example, as a layer that propagates polarized spins.

[0149] For example, the first non-magnetic layer 41 may be in contact with the first magnetic layer 21 and the second magnetic pole 32. The second non-magnetic layer 42 may be in contact with the second magnetic layer 22 and the first magnetic layer 21. The third non-magnetic layer 43 may be in contact with the third magnetic layer 23 and the second magnetic layer 22. The fourth non-magnetic layer 44 may be in contact with the first magnetic pole 31 and the third magnetic layer 23.

[0150] The magnetic head 120A may also perform the operations described with reference to Figures 13(a) and 13(b). As shown in Figure 13(b), the magnetic head 120A also has an electrical resistance Rz2 of the laminate 20 when the current jc1 flowing through the laminate 20 is a first current i1. The first current i1 is in a first current range ir1.

[0151] 13(b), in the magnetic head 120A, when the current jc1 flowing through the laminate 20 is the second current i2, the electrical resistance Rz2 of the laminate 20 is the second resistance R2. The second current i2 is larger than the first current i1. The second current i2 is in the second current range ir2. The second resistance R2 is higher than the first resistance R1.

[0152] At a third current i3 between the first current i1 and the second current i2, the electrical resistance Rz2 of the laminate 20 is a third resistance R3. The third current i3 is in a third current range ir3.

[0153] In the magnetic head 120A, for example, when the current jc1 is the first current i1 or the second current i2, the electric resistance Rz2 does not substantially oscillate. For example, when the current jc1 is the third current i3, the electric resistance Rz2 oscillates. The first current i1, the second current i2, and the third current i3 are oriented from the first magnetic layer 21 to the second magnetic layer 22.

[0154] In the third embodiment, in a recording operation in which information is recorded on the magnetic recording medium 80 using the magnetic head 120A, the electric circuit 20D can supply the above-mentioned second current i2 to the stack 20. By performing a recording operation in which the recording circuit 30D supplies the recording current Iw to the coil while supplying the above-mentioned second current i2, it is possible to increase the amount of the recording magnetic field directed from the first magnetic pole 31 to the magnetic recording medium 80, compared to a case in which the recording operation is performed without supplying the second current i2. The recording gap that allows good recording can be made smaller. According to the third embodiment, it is possible to provide a magnetic recording device that allows for improved recording density.

[0155] An example of the characteristics of a magnetic recording device will now be described. FIG. 19 is a schematic diagram illustrating the characteristics of a magnetic recording device. 19 illustrates simulation results of the characteristics of the magnetic head including the stack 20 under the fourth condition CH4, the fifth condition CH5, and the sixth condition CH6. Under the fourth condition CH4, the configuration of the magnetic head 120A described above is applied. That is, the second nonmagnetic layer 42 is made of Cu, and the second nonmagnetic layer 42 propagates, for example, polarized spins.

[0156] Under the fifth condition CH5, the second nonmagnetic layer 42 is made of Ta, and the second nonmagnetic layer 42 damps, for example, polarized spins. The other configurations under the fifth condition CH5 are similar to the configurations under the fourth condition CH4.

[0157] Under the sixth condition CH6, the second nonmagnetic layer 42 is not provided, and the first magnetic layer 21 and the second magnetic layer 22 are in contact with each other. Other configurations under the sixth condition CH6 are similar to the configurations under the fourth condition CH4.

[0158] The horizontal axis in Fig. 19 is time tm. At a first time tm1 (see Fig. 15: when time tm is 0.60 ns), the polarity of the recording current Iw is reversed. The vertical axis in Fig. 19 is parameter P1 corresponding to the amount of magnetization reversal. In the fourth condition CH4, the fifth condition CH5 and the sixth condition CH6, the parameter P1 corresponds to the amount of magnetization reversal existing between the first magnetic pole 31 and the second magnetic pole 32.

[0159] 19 also illustrates the characteristic PM of the magnetization direction of the first magnetic pole 31. With respect to the characteristic PM, a parameter P1 corresponds to the magnetization direction of the first magnetic pole 31. In the example of FIG. 19, the polarity of the recording current Iw is reversed at a first time tm1 (when the time tm is 0.60 ns). When the time tm is 0.62 ns, the magnetization direction of the first magnetic pole 31 starts to change. When the time tm is 0.67 ns, the change in the magnetization direction of the first magnetic pole 31 essentially ends.

[0160] 19, in the fourth condition CH4, the parameter P1 is larger when the time tm is 0.7 ns or later than in the fifth condition CH5 and the sixth condition CH6. In the fourth condition CH4, the magnetization existing between the first magnetic pole 31 and the second magnetic pole 32 is substantially reversed with respect to the magnetization of the first magnetic pole 31. In the fourth condition CH4, a magnetic material with a large magnetized volume that reverses at high speed can be reversed. In particular, in the fourth condition CH4, the OW (Over Write) characteristics in magnetic recording can be improved.

[0161] In the third embodiment, the configuration of the magnetic head 120A described above is applied. This effectively improves the recording capability even at a relatively high recording frequency, and improves the recording characteristics. According to the second embodiment, a magnetic recording device capable of improving the recording density can be provided.

[0162] In the magnetic head 120A, the first to third magnetic layers 21 to 23 have thicknesses t21 to t23, respectively (see FIG. 16). In the magnetic head 120A, the first to fourth non-magnetic layers 41 to 44 have thicknesses t41 to t44 (see FIG. 16).

[0163] In the magnetic head 120A, the thickness t21 of the first magnetic layer 21 is, for example, 2 nm or more and 10 nm or less. When the thickness t21 is 2 nm or more, for example, the magnetic field toward the magnetic recording medium 80 can be effectively increased. When the thickness t21 is 8 nm or less, for example, efficient magnetization reversal can be easily obtained.

[0164] In the magnetic head 120A, the thickness t22 of the second magnetic layer 22 is, for example, 2 nm or more and 4 nm or less. If the thickness t22 is 2 nm or more, it is easy to obtain a higher gain during high-speed operation. If the thickness t22 is 4 nm or less, it is easy to obtain stable operation.

[0165] In the magnetic head 120A, the thickness t23 of the third magnetic layer 23 is, for example, 2 nm or more and 5 nm or less. When the thickness t23 is 2 nm or more, for example, electrons passing through the third magnetic layer 23 are easily spin-polarized. When the thickness t23 is 5 nm or less, for example, the magnetization of the third magnetic layer 23 is easily stabilized.

[0166] In the magnetic head 120A, the thickness t41 of the first nonmagnetic layer 41 is, for example, not less than 1 nm and not more than 5 nm. When the thickness t41 is in this range, for example, spin can be effectively propagated.

[0167] In the magnetic head 120A, the thickness t42 of the second nonmagnetic layer 42 is, for example, not less than 1 nm and not more than 5 nm. When the thickness t42 is in this range, for example, spin can be effectively propagated.

[0168] In the magnetic head 120A, the thickness t43 of the third nonmagnetic layer 43 is, for example, not less than 1 nm and not more than 5 nm. When the thickness t43 is in this range, for example, spin can be effectively propagated.

[0169] In the magnetic head 120A, the thickness t44 of the fourth nonmagnetic layer 44 is, for example, not less than 1 nm and not more than 5 nm. When the thickness t44 is in this range, for example, spin can be effectively propagated.

[0170] FIG. 20 is a schematic cross-sectional view illustrating a portion of the magnetic recording device according to the third embodiment. 20, the magnetic head 121A according to the third embodiment does not include the fourth nonmagnetic layer 44. In the magnetic head 121A, the first magnetic pole 31 is in contact with the third magnetic layer 23. Other configurations of the magnetic head 121A may be similar to those of the magnetic head 120A.

[0171] In the magnetic head 121A, the magnetization existing between the first magnetic pole 31 and the second magnetic pole 32 also reverses with respect to the magnetization of the first magnetic pole 31. A magnetic body having a large magnetized volume that reverses at high speed can be reversed. According to the second embodiment, a magnetic recording device capable of improving recording density can be provided.

[0172] In the magnetic head 120A and the magnetic head 121A, the second nonmagnetic layer 42 and the third nonmagnetic layer 43 preferably contain Cr, which makes it easier to improve the amount of propagated spin, for example.

[0173] The second and third embodiments may include the following configurations (for example, technical solutions). (Configuration A1) A first magnetic pole; A second magnetic pole; a laminate provided between the first magnetic pole and the second magnetic pole; Including, The laminate comprises: A first magnetic layer; a second magnetic layer provided between the first magnetic pole and the first magnetic layer; a third magnetic layer provided between the first magnetic pole and the second magnetic layer; a first non-magnetic layer provided between the first magnetic layer and the second magnetic pole; a second nonmagnetic layer provided between the second magnetic layer and the first magnetic layer; a third nonmagnetic layer provided between the third magnetic layer and the second magnetic layer; Including, the first magnetic layer includes at least one of Fe, Co, and Ni; the second magnetic layer includes at least one of Fe, Co, and Ni; the third magnetic layer includes a first element including at least one of Fe, Co, and Ni, and a second element including at least one selected from the group consisting of Cr, V, Mn, Ti, and Sc, the first magnetic layer and the second magnetic layer do not include the second element, or a concentration of the second element in the first magnetic layer and the second magnetic layer is lower than a concentration of the second element in the third magnetic layer, the first nonmagnetic layer includes at least one selected from the group consisting of Cu, Ag, Au, Al, and Cr; the second nonmagnetic layer includes at least one selected from the group consisting of Ta, Pt, W, Mo, Ir, Ru, Tb, Rh, Cr, and Pd; The magnetic head, wherein the third nonmagnetic layer contains at least one selected from the group consisting of Cu, Ag, Au, Al, and Cr.

[0174] (Configuration A2) The magnetic head according to configuration A1, wherein the third nonmagnetic layer contains Cr.

[0175] (Configuration A3) A first magnetic pole; A second magnetic pole; a laminate provided between the first magnetic pole and the second magnetic pole; Including, The laminate comprises: A first magnetic layer; a second magnetic layer provided between the first magnetic pole and the first magnetic layer; a third magnetic layer provided between the first magnetic pole and the second magnetic layer; a first non-magnetic layer provided between the first magnetic layer and the second magnetic pole; a second nonmagnetic layer provided between the second magnetic layer and the first magnetic layer; a third nonmagnetic layer provided between the third magnetic layer and the second magnetic layer; Including, the first magnetic layer includes a first element including at least one of Fe, Co, and Ni, and a second element including at least one selected from the group consisting of Cr, V, Mn, Ti, and Sc; the second magnetic layer includes at least one of Fe, Co, and Ni, and the second magnetic layer does not include the second element, or the concentration of the second element in the second magnetic layer is lower than the concentration of the second element in the first magnetic layer; the third magnetic layer includes a third element including at least one of Fe, Co, and Ni, and a fourth element including at least one selected from the group consisting of Cr, V, Mn, Ti, and Sc, the second magnetic layer does not include the fourth element, or the concentration of the fourth element in the second magnetic layer is lower than the concentration of the fourth element in the third magnetic layer, the first nonmagnetic layer includes at least one selected from the group consisting of Cu, Ag, Au, Al, and Cr; the second nonmagnetic layer includes at least one selected from the group consisting of Cu, Ag, Au, Al, and Cr; The magnetic head, wherein the third nonmagnetic layer contains at least one selected from the group consisting of Cu, Ag, Au, Al, and Cr.

[0176] (Configuration A4) The magnetic head according to structure A3, wherein the second nonmagnetic layer and the third nonmagnetic layer contain Cr.

[0177] (Configuration A5) the first nonmagnetic layer is in contact with the first magnetic layer and the second magnetic pole, the second nonmagnetic layer is in contact with the second magnetic layer and the first magnetic layer, The magnetic head according to any one of configurations A1 to A4, wherein the third nonmagnetic layer is in contact with the third magnetic layer and the second magnetic layer.

[0178] (Configuration A6) The magnetic head according to any one of configurations A1 to A5, wherein the first magnetic pole is in contact with the third magnetic layer.

[0179] (Configuration A7) the stack further includes a fourth nonmagnetic layer, the fourth nonmagnetic layer is provided between the first magnetic pole and the third magnetic layer, The magnetic head according to any one of structures A1 to A6, wherein the fourth nonmagnetic layer includes at least one selected from the group consisting of Cu, Ag, Au, Al, and Cr.

[0180] (Configuration A8) The magnetic head according to configuration A7, wherein the fourth nonmagnetic layer is in contact with the first magnetic pole and the third magnetic layer.

[0181] (Configuration A9) The magnetic head according to structure A7 or A8, wherein the fourth nonmagnetic layer has a thickness of 1 nm or more and 5 nm or less.

[0182] (Configuration A10) The magnetic head according to any one of configurations A1 to A9, wherein the second current has a direction from the first magnetic layer to the second magnetic layer.

[0183] (Configuration A11) The magnetic head according to any one of structures A1 to A10, wherein the first nonmagnetic layer has a thickness of not less than 1 nm and not more than 5 nm.

[0184] (Configuration A12) The magnetic head according to any one of structures A1 to A11, wherein the second nonmagnetic layer has a thickness of 1 nm or more and 5 nm or less.

[0185] (Configuration A13) The magnetic head according to any one of structures A1 to A12, wherein the third nonmagnetic layer has a thickness of not less than 1 nm and not more than 5 nm.

[0186] (Configuration A14) The magnetic head according to any one of structures A1 to A13, wherein the first magnetic layer has a thickness of not less than 2 nm and not more than 8 nm.

[0187] (Configuration A15) The magnetic head according to any one of configurations A1 to A14, wherein the second magnetic layer has a thickness of 2 nm or more and 5 nm or less.

[0188] (Configuration A16) The magnetic head according to any one of structures A1 to A15, wherein the third magnetic layer has a thickness of not less than 2 nm and not more than 5 nm.

[0189] (Configuration A17) A magnetic head according to any one of configurations A1 to A16, A magnetic recording medium; An electric circuit; Preparation, an electrical resistance of the laminate when a current flowing through the laminate is a first current is a first resistance; when the current flowing through the stack is a second current greater than the first current, the electrical resistance of the stack is a second resistance greater than the first resistance, when the current flowing through the stack is a third current between the first current and the second current, the electrical resistance of the stack oscillates; A magnetic recording device, wherein the electric circuit is capable of supplying the second current to the stack during a recording operation for recording information on the magnetic recording medium using the magnetic head.

[0190] FIG. 21 is a graph illustrating the characteristics of the magnetic layer included in the magnetic head. FIG. 21 shows a parameter P1 corresponding to the amount of magnetization reversal when the composition of the third magnetic layer 23 is changed in the configuration of the magnetic head 110A. In this example, the composition ratio y is 20 atm%, and the composition ratio x of Co is changed. The second element E is Cr. The horizontal axis of FIG. 21 is the composition ratio x. The vertical axis is the parameter P1. In this example, the parameter P1 is a value 0.1 ns after the polarity of the recording current Iw is reversed. In FIG. 21, when the parameter P1 is positive and large, it corresponds to high speed magnetization reversal. In FIG. 21, when the parameter P1 is positive and large, high recording density is obtained. As can be seen from FIG. 21, a large parameter P1 is obtained when the composition ratio x is 10 atm% or more and 50 atm% or less. Under this condition, for example, magnetization can be reversed at high speed, and highly efficient recording can be performed. This makes it easy to improve the recording density. It is more preferable that the composition ratio x is 25 atm% or more and 35 atm% or less. High speed reversal is stable and easy to obtain.

[0191] In the magnetic head according to the second embodiment (magnetic heads 110A and 111A), the third magnetic layer 23 (for example, a magnetic layer having negative spin polarization) is (Fe 100-x Co x ) 100-y E y (10 atm%≦x≦50 atm%, 10 atm%≦y≦90 atm%). The second element E includes at least one selected from the group consisting of Cr, V, Mn, Ti, and Sc. The composition ratio x and the composition ratio y are atomic percent (atm%). This makes it easy to obtain, for example, a high saturation magnetic flux density and a negative spin polarization with a large absolute value. Efficient magnetization reversal is obtained. The recording density can be improved.

[0192] FIG. 22 is a graph illustrating the characteristics of the magnetic layer included in the magnetic head. FIG. 22 shows a parameter P1 corresponding to the amount of magnetization reversal when the composition of the first magnetic layer 21 and the third magnetic layer 23 is changed in the configuration of the magnetic head 120A. In this example, the composition ratio y is 20 atm%, and the composition ratio x of Co is changed. The second element E is Cr. In this example, the composition ratio x and the composition ratio y in the first magnetic layer 21 are the same as the composition ratio x and the composition ratio y in the third magnetic layer 23, respectively. The horizontal axis of FIG. 22 is the composition ratio x. The vertical axis is the parameter P1. In FIG. 22, the parameter P1 is a value 0.1 ns after the polarity of the recording current Iw is reversed. As can be seen from FIG. 22, a large parameter P1 is obtained when the composition ratio x is 10 atm% or more and 50 atm% or less. Under this condition, for example, the magnetization can be reversed at high speed, and highly efficient recording can be performed. This makes it easy to improve the recording density. It is more preferable that the composition ratio x is 25 atm% or more and 35 atm% or less. High speed reversal is stable and easy to obtain.

[0193] In the magnetic head according to the third embodiment (magnetic heads 120A and 121A), , No. The first magnetic layer 21 and the third magnetic layer 23 (e.g., a magnetic layer having a negative spin polarization) are 100-x Co x ) 100-y E y It is preferable that the composition ratio of the third magnetic layer 23 includes (10 atm%≦x≦50 atm%, 10 atm%≦y≦90 atm%). This makes it easy to obtain, for example, a high saturation magnetic flux density and a negative spin polarization with a large absolute value. Efficient magnetization reversal is obtained. Recording density can be improved. The composition ratio of the third magnetic layer 23 may be different from that of the first magnetic layer 21. For example, the third magnetic layer 23 may include (Fe 100-x1 Co x1 ) 100-y1 EX y1 (10 atm%≦x1≦50 atm%, 10 atm%≦y1≦90 atm%), and the fourth element EX includes at least one selected from the group consisting of Cr, V, Mn, Ti, and Sc.

[0194] (Fourth embodiment) FIG. 23 is a schematic cross-sectional view illustrating the magnetic head according to the fourth embodiment. The magnetic recording device 210 according to the fourth embodiment also includes a magnetic head 110B and an electric circuit 20D. The magnetic recording device 210 may include a magnetic recording medium 80. In the magnetic recording device 210, for example, at least a recording operation is performed. In the recording operation, information is recorded on the magnetic recording medium 80 using the magnetic head 110B.

[0195] In this example, the electric circuit 20D (see FIG. 2) is also electrically connected to the laminate 20S. In this example, the laminate 20S is electrically connected to the first magnetic pole 31 and the second magnetic pole 32. A first terminal T1 and a second terminal T2 are provided on the magnetic head 110B. The first terminal T1 is electrically connected to the laminate 20S via the first wiring W1 and the first magnetic pole 31. The second terminal T2 is electrically connected to the laminate 20S via the second wiring W2 and the second magnetic pole 32. For example, a current Is (for example, a direct current) is supplied to the laminate 20S from the electric circuit 20D.

[0196] As shown in FIG. 23, the stacked body 20S includes a first magnetic layer 21, a second magnetic layer 22, a third magnetic layer 23, a first non-magnetic layer 41, a second non-magnetic layer 42 and a third non-magnetic layer 43.

[0197] The first magnetic layer 21 is between the first magnetic pole 31 and the second magnetic pole 32. The second magnetic layer 22 is provided between the first magnetic pole 31 and the first magnetic layer 21. The third magnetic layer 23 is provided between the first magnetic pole 31 and the second magnetic layer 22.

[0198] The first nonmagnetic layer 41 is provided between the second magnetic layer 22 and the first magnetic layer 21. The first nonmagnetic layer 41 contains Cu. The first nonmagnetic layer 41 is, for example, a Cu layer.

[0199] The second nonmagnetic layer is provided between the third magnetic layer and the second magnetic layer 22. The third nonmagnetic layer 43 is provided between the first magnetic pole 31 and the third magnetic layer .

[0200] In this example, the first magnetic layer 21 is in contact with the second magnetic pole 32. The first non-magnetic layer 41 is in contact with the second magnetic layer 22 and the first magnetic layer 21. The second non-magnetic layer 42 is in contact with the third magnetic layer 23 and the second magnetic layer 22. The third non-magnetic layer 43 is in contact with the first magnetic pole 31 and the third magnetic layer 23.

[0201] The second magnetic layer 22 includes a first magnetic region 22a and a second magnetic region 22b. The second magnetic region 22b is between the second nonmagnetic layer 42 and the first magnetic region 22a. The first magnetic region 22a is a region on the first nonmagnetic layer 41 side. The second magnetic region 22b is a region on the second nonmagnetic layer 42 side. For example, the first magnetic region 22a contacts the first nonmagnetic layer 41. For example, the second magnetic region 22b contacts the second nonmagnetic layer 42.

[0202] The first magnetic region 22a includes a first element including at least one of Fe, Co, and Ni. The second magnetic region 22b includes a first element and a second element. The second element includes at least one selected from the group consisting of Cr, V, Mn, Ti, and Sc. When the second magnetic region 22b includes such a material, for example, the second magnetic region 22b has a negative spin polarization. The first magnetic region 22a does not include the second element. Or, the concentration of the second element in the first magnetic region 22a is lower than the concentration of the second element in the second magnetic region 22b. When the first magnetic region 22a includes such a material, the first magnetic region 22a has a positive spin polarization.

[0203] In one example, the concentration of the second element in the first magnetic region 22a is substantially 0 atomic %. For example, the concentration of the second element in the first magnetic region 22a may be 0 atomic % or more and less than 20 atomic %. For example, the concentration of the second element in the second magnetic region 22b is 20 atomic % or more and 50 atomic % or less.

[0204] As already described, a current Is is supplied from the electric circuit 20D to the stack 20S (see FIG. 2). As shown in FIG. 23, a current jc1 (current Is) flowing through the stack 20S is directed from the first magnetic layer 21 to the third magnetic layer 23. An electron current je1 is directed from the third magnetic layer 23 to the first magnetic layer 21.

[0205] For example, when current jc1 is not supplied to the stack 20S, the magnetization directions of the first magnetic layer 21, the second magnetic layer 22, and the third magnetic layer 23 are substantially the same as the magnetization directions of the first magnetic pole 31 and the second magnetic pole 32. A part of the magnetic field (recording magnetic field) emitted from the first magnetic pole 31 is directed toward the magnetic recording medium 80. On the other hand, another part of the magnetic field (recording magnetic field) emitted from the first magnetic pole 31 passes through the stack 20S and enters the second magnetic pole 32 without being directed toward the magnetic recording medium 80. Therefore, the proportion of the part of the recording magnetic field emitted from the first magnetic pole 31 that is directed toward the magnetic recording medium 80 is small.

[0206] When the current jc1 is supplied to the laminate 20S, for example, the magnetization direction of at least a part of the laminate 20S (for example, at least a part of the second magnetic layer 22 and the third magnetic layer 23) is reversed with respect to the magnetization direction of the first magnetic pole 31 and the magnetization direction of the second magnetic pole 32. As a result, the magnetic field (recording magnetic field) emitted from the first magnetic pole 31 is less likely to be directed toward the laminate 20S. Therefore, the proportion of the portion of the recording magnetic field emitted from the first magnetic pole 31 that is directed toward the magnetic recording medium 80 becomes higher than when the current jc1 is not supplied to the laminate 20S. The recording magnetic field emitted from the first magnetic pole 31 is effectively applied to the magnetic recording medium 80.

[0207] This phenomenon becomes more pronounced as the distance (recording gap) between the first magnetic pole 31 and the second magnetic pole 32 becomes shorter. By using such a laminate 20S, good recording can be performed even when the recording gap becomes small. According to the fourth embodiment, the recording gap that allows good recording can be made small. According to the fourth embodiment, it is possible to provide a magnetic recording device that can improve the recording density.

[0208] On the other hand, there is Microwave Assisted Magnetic Recording (MAMR), in which a high-frequency magnetic field generated from a laminate including multiple magnetic layers is applied to a magnetic recording medium 80 to locally control the magnetic properties of the magnetic recording medium 80 for recording. In MAMR, a high-frequency magnetic field is generated by oscillation of the magnetization of the magnetic layers.

[0209] In contrast, in the fourth embodiment, for example, the magnetization of at least a part of the laminate 20S is reversed with respect to the magnetization of the first magnetic pole 31 and the magnetization of the second magnetic pole 32. The magnetic field generated from the first magnetic pole 31 is efficiently applied to the magnetic recording medium 80 by an operation different from MAMR.

[0210] In the fourth embodiment, the second magnetic layer 22 includes a first magnetic region 22a and a second magnetic region 22b. With this configuration, the recording magnetic field generated from the first magnetic pole 31 is applied to the magnetic recording medium 80 more stably and effectively.

[0211] An example of an experimental result in the case where the second magnetic layer 22 does not include the first magnetic region 22a and the second magnetic region 22b will be described below.

[0212] FIG. 24 is a schematic cross-sectional view illustrating an experimental sample. FIG. 25 is a graph illustrating the experimental results. As shown in FIG. 24, the experimental sample includes a first magnetic layer 21, a second magnetic layer 22, and a first non-magnetic layer 41. The first non-magnetic layer 41 is between the first magnetic layer 21 and the second magnetic layer 22. The first magnetic layer 21 is an FeCo layer. The first non-magnetic layer 41 is a Cu layer. In the first sample, the second magnetic layer 22 includes FeCr. In the second sample, the second magnetic layer 22 includes FeCo. In the first sample, the second magnetic layer 22 has a negative spin polarization. In the second sample, the second magnetic layer 22 has a positive spin polarization.

[0213] A current oriented from the first terminal TM1 to the second terminal TM2 is supplied to such a sample while applying a magnetic field. The magnetic field is oriented from the second magnetic layer 22 to the first magnetic layer 21. The relationship between the variation in magnetization of the first magnetic layer 21 and the strength of the magnetic field is examined.

[0214] The horizontal axis of Fig. 25 is the strength H1 of the magnetic field. The vertical axis of Fig. 25 is the current density CD at which the magnetic field of the first magnetic layer 21 starts to vary. As shown in Fig. 25, in the first sample SP1, the current density CD at which the magnetic field of the first magnetic layer 21 starts to vary is low. In the second sample SP2, the current density CD at which the magnetic field of the first magnetic layer 21 starts to vary is high. It is considered that the magnetization of the first magnetic layer 21 is unstable in the first sample SP1.

[0215] In the first sample SP1, it is believed that the magnetization of the first magnetic layer 21 becomes unstable due to the transmitted spin transfer torque (STT) acting on the first magnetic layer 21 from the second magnetic layer 22 having negative polarization.

[0216] In the fourth embodiment, the second magnetic layer 22 is provided with a first magnetic region 22a and a second magnetic region 22b. The first magnetic region 22a has, for example, a positive spin polarization. Therefore, the STT is suppressed from acting on the first magnetic layer 21, and the magnetization of the first magnetic layer 21 is stabilized. It is considered that the magnetization of the first magnetic layer 21 is stabilized, and the magnetization of the second magnetic layer 22 and the third magnetic layer 23 can be stably reversed by the STT from the first magnetic layer 21. As a result, in the fourth embodiment, the recording magnetic field from the first magnetic pole 31 is applied to the magnetic recording medium 80 more stably and effectively. A magnetic head capable of improving the recording density can be provided.

[0217] An example of magnetization reversal will now be described. 26(a) to 26(c) are schematic views illustrating the magnetic head according to the fourth embodiment. In these figures, the magnetization of the first magnetic pole 31 and the second magnetic pole 32 has a direction from the first magnetic pole 31 to the second magnetic pole 32.

[0218] 26(a), when the current jc1 is not supplied to the stack 20S, the magnetization 21M of the first magnetic layer 21, the magnetization 22M of the second magnetic layer 22, and the magnetization of the third magnetic layer 23 are oriented in the same direction as the magnetization of the first magnetic pole 31 and the second magnetic pole 32 (the direction from the first magnetic pole 31 to the second magnetic pole 32). The direction of the electron current je1 is from the second magnetic pole 32 to the first magnetic pole 31.

[0219] As shown in FIG. 26(b), when a current jc1 equal to or greater than a threshold value is supplied to the stack 20S, a regular spin transfer torque S1 from the first magnetic region 22a acts on the first magnetic layer 21, and the magnetization 21M of the first magnetic layer 21 is stabilized.

[0220] As shown in FIG. 26(c), the magnetization 22M of the second magnetic layer 22 is reversed by the positively reflected spin transfer torque S2 from the first magnetic layer 21. The magnetization 23M of the third magnetic layer 23 is reversed by the negatively reflected spin transfer torque S3 from the reversed magnetization 21M. In this manner, for example, the magnetization 22M of the second magnetic layer 22 and the magnetization 23M of the third magnetic layer 23 are stably reversed with respect to the magnetizations of the first magnetic pole 31 and the second magnetic pole 32. This allows the recording magnetic field from the first magnetic pole 31 to be effectively applied to the magnetic recording medium 80. A magnetic head capable of improving recording density can be provided. Recording performance is improved.

[0221] In the fourth embodiment, the first magnetic layer 21 includes, for example, Fe and Co. The first magnetic layer 21 has, for example, positive spin polarization.

[0222] In the magnetic head 110B, the third magnetic layer 23 includes, for example, the first element and the second element. The third magnetic layer 23 has, for example, a negative spin polarization. As will be described later, the third magnetic layer 23 may have a positive spin polarization.

[0223] As already explained, the first nonmagnetic layer 41 contains Cu, which allows the spin transfer torque to be transmitted efficiently.

[0224] The second nonmagnetic layer 42 contains, for example, Cu. The second nonmagnetic layer 42 may contain Cu and the above-mentioned second element.

[0225] In the example of FIG. 23, the third nonmagnetic layer 43 includes, for example, at least one selected from the group consisting of Ta, Ru, and Cr.

[0226] 23, in the magnetic head 110B, the first magnetic layer 21 has a thickness t21. The first magnetic region 22a has a thickness t22a. The second magnetic region 22b has a thickness t22b. The third magnetic layer 23 has a thickness t23. In the magnetic head 110B, the first to third non-magnetic layers 41 to 43 have thicknesses t41 to t43 (see FIG. 23).

[0227] In the magnetic head 110B, the thickness t22a of the first magnetic region 22a is preferably, for example, 0.5 nm or more and 10 nm or less. When the thickness t22a is 0.5 nm or more, for example, the STT can be effectively reduced. When the thickness t22a is 10 nm or less, for example, the reversal current is prevented from becoming excessively large, for example, high reliability can be obtained. The thickness t22a may be 0.3 nm or less. This effectively improves the recording ability due to the reversal of magnetization.

[0228] The thickness t22b of the second magnetic region 22b is preferably, for example, 2 nm or more and 7 nm or less. When the thickness t22b is 2 nm or more, for example, a large spin transfer torque can be obtained, and the magnetization 23M of the third magnetic layer 23 can be effectively reversed by the action of the second magnetic region 22b. When the thickness t22b is 7 nm or less, for example, the hardness of the second magnetic region 22b can be prevented from becoming excessively high. This makes it easier to process the stack 20S.

[0229] The thickness of the second magnetic layer 22 (for example, the sum of the thickness t22a and the thickness t22b) is preferably, for example, not less than 3 nm and not more than 10 nm.

[0230] The thickness t21 of the first magnetic layer 21 is preferably, for example, 1 nm or more and 3 nm or less. When the thickness t21 is 1 nm or more, for example, the magnetization 21M of the first magnetic layer 21 becomes stable. When the thickness t21 is 3 nm or less, for example, the gap length (the distance between the first magnetic pole 31 and the second magnetic pole 32) can be prevented from becoming excessively large. For example, a high recording density can be easily obtained.

[0231] The thickness t23 of the third magnetic layer 23 is preferably, for example, 1 nm or more and 5 nm or less. When the thickness t23 is 1 nm or more, for example, it is possible to suppress an extreme decrease in the magnetization of the third magnetic layer 23. When the thickness t23 is 5 nm or less, for example, it is possible to easily reverse the magnetization 23M of the third magnetic layer 23.

[0232] The thickness t41 of the first nonmagnetic layer 41 is preferably, for example, 1 nm or more and 5 nm or less. When the thickness t41 is 1 nm or more, for example, the magnetic separation between the first magnetic layer 21 and the second magnetic layer 22 is stabilized. When the thickness t41 is 5 nm or less, for example, the processing of the stack 20S is facilitated.

[0233] The thickness t42 of the second nonmagnetic layer 42 is preferably, for example, 1 nm or more and 5 nm or less. When the thickness t42 is 1 nm or more, for example, the magnetic separation between the second magnetic layer 22 and the third magnetic layer 23 is stabilized. When the thickness t42 is 5 nm or less, for example, the processing of the stack 20S is facilitated.

[0234] 23, the thickness t43 of the third nonmagnetic layer 43 is preferably, for example, 1 nm or more and 5 nm or less. When the thickness t43 is 1 nm or more, for example, magnetic separation of both sides in the X-axis direction of the third nonmagnetic layer 43 is facilitated. When the thickness t43 is 5 nm or less, for example, transmission of STT is facilitated.

[0235] FIG. 27 is a schematic cross-sectional view illustrating the magnetic head according to the fourth embodiment. 27, in a magnetic head 111B according to the fourth embodiment, a stack 20S includes a fourth magnetic layer 24 in addition to the first to third magnetic layers 21-23 and the first to third non-magnetic layers 41-43. In the magnetic head 111B, the third magnetic layer 23 has positive spin polarization. Except for the above, the configuration of the magnetic head 111B may be similar to the configuration of the magnetic head 110B.

[0236] The fourth magnetic layer 24 is between the first magnetic pole 31 and the third non-magnetic layer 43. The fourth magnetic layer 24 includes, for example, a first element and a second element. For example, the concentration of the second element in the fourth magnetic layer 24 is 20 atomic % or more and 50 atomic % or less. For example, the third magnetic layer 23 includes the above-mentioned first element. The third magnetic layer 23 is, for example, an FeCo layer. The third magnetic layer 23 does not include the above-mentioned second element. Alternatively, the concentration of the second element in the third magnetic layer 23 is lower than the concentration of the second element in the second magnetic region 22b. In one example, the fourth magnetic layer 24 contacts the first magnetic pole 31 and is magnetically coupled to the first magnetic pole 31. For example, a layer that magnetically couples the first magnetic pole 31 and the fourth magnetic layer 24 may be provided between the first magnetic pole 31 and the fourth magnetic layer 24.

[0237] In such a magnetic head 111B as well, the magnetization 21M of the first magnetic layer 21 becomes stable. For example, the magnetization of the second magnetic layer 22 and the magnetization 23M of the third magnetic layer 23 can be stably reversed. The recording magnetic field generated from the first magnetic pole 31 is effectively applied to the magnetic recording medium 80. A magnetic head capable of improving the recording density can be provided.

[0238] 27, the third nonmagnetic layer 43 contains, for example, Cu. The third nonmagnetic layer 43 may further contain a second element. The third nonmagnetic layer 43 preferably has a thickness t43 of, for example, not less than 1 nm and not more than 5 nm.

[0239] In the example of FIG. 27, the thickness t24 of the fourth magnetic layer 24 is preferably, for example, 2 nm or more and 5 nm or less. When the thickness t24 is 2 nm or more, for example, negative polarization can be stably obtained in the fourth magnetic layer 24. When the thickness t24 is 5 nm or less, for example, it is possible to prevent the gap length from becoming excessively large. It is possible to prevent a decrease in the steepness of the recording magnetic field. For example, it is easy to obtain a high recording density.

[0240] FIG. 28 is a schematic cross-sectional view illustrating the magnetic head according to the fourth embodiment. 28, in the magnetic head 112B according to the fourth embodiment, the stack 20S also includes a fourth magnetic layer 24 and a fourth nonmagnetic layer 44 in addition to the first to third magnetic layers 21-23 and the first to third nonmagnetic layers 41-43. In the magnetic head 112B, the third magnetic layer 23 has negative spin polarization. Except for the above, the configuration of the magnetic head 112B may be similar to the configuration of the magnetic head 110B.

[0241] The fourth magnetic layer 24 is between the first magnetic pole 31 and the third non-magnetic layer 43. The fourth magnetic layer 24 includes, for example, a first element and a second element. The concentration of the second element in the fourth magnetic layer 24 is not less than 20 atomic % and not more than 50%. For example, the third magnetic layer 23 includes the first element and the second element. For example, the concentration of the second element in the third magnetic layer 23 is not less than 20 atomic % and not more than 50%.

[0242] The fourth nonmagnetic layer 44 is located between the first magnetic pole 31 and the fourth magnetic layer 24. The fourth nonmagnetic layer 44 includes at least one selected from the group consisting of Ta, Ru, and Cr.

[0243] In such a magnetic head 112B as well, the magnetization 21M of the first magnetic layer 21 becomes stable. For example, the magnetization of the second magnetic layer 22 and the magnetization 23M of the third magnetic layer 23 can be stably reversed. The recording magnetic field generated from the first magnetic pole 31 is effectively applied to the magnetic recording medium 80. A magnetic head capable of improving the recording density can be provided.

[0244] In the example of FIG. 28, the thickness t24 of the fourth magnetic layer 24 is preferably, for example, 1 nm or more and 5 nm or less. When the thickness t24 is 1 nm or more, for example, the magnetic coupling between the magnetic pole 31 and the fourth magnetic layer 24 can be stably suppressed. For example, the transmission and reception of STT between the magnetic pole 31 and the fourth magnetic layer 24 can be stably suppressed. When the thickness t24 is 5 nm or less, for example, the gap length can be suppressed from becoming excessively large. A decrease in the steepness of the recording magnetic field can be suppressed. For example, a high recording density can be easily obtained.

[0245] In the fourth embodiment, the characteristics described with reference to Figs. 13(a) and 13(b) can be obtained. When the current jc1 increases, the electrical resistance Rz1 increases. The magnitude of the current jc1 can be divided into a first current range ir1, a second current range ir2, and a third current range ir3. The third current range ir3 is between the first current range ir1 and the second current range ir2.

[0246] In the first current range ir1 and the second current range ir2, the electrical resistance Rz1 changes according to a quadratic function with respect to the magnitude of the current jc1, which is believed to be due to the fact that the temperature of the laminate 20S increases as the current jc1 increases.

[0247] The change in the electrical resistance Rz1 in the third current range ir3 is not influenced by an increase in temperature, and is considered to be due to the magnetoresistance effect based on the reversal rate of the magnetization of the magnetic layer.

[0248] For example, when the effect of the quadratic function on the electrical resistance is removed, the electrical resistance Rz2 is substantially constant in the first current range ir1. Or, the electrical resistance Rz2 changes more slowly in the first current range ir1 than in the third current range ir3. The electrical resistance Rz2 changes in the third current range ir3. The electrical resistance Rz2 is substantially constant in the second current range ir2. Or, the electrical resistance Rz2 changes more slowly in the second current range ir2 than in the third current range ir3.

[0249] For example, when the current jc1 flowing through the laminate 20S is a first current i1, the electrical resistance Rz2 of the laminate 20S is the first resistance R1. The first current i1 is in a first current range ir1.

[0250] When the current jc1 flowing through the laminate 20S is the second current i2, the electrical resistance Rz2 of the laminate 20S is the second resistance R2. The second current i2 is greater than the first current i1. The second current i2 is in a second current range ir2. The second resistance R2 is higher than the first resistance R1.

[0251] At a third current i3 between the first current i1 and the second current i2, the electrical resistance Rz2 of the laminate 20S is a third resistance R3. The third current i3 is in a third current range ir3.

[0252] For example, when the current jc1 is the first current i1 or the second current i2, the electrical resistance Rz2 does not substantially oscillate. For example, when the current jc1 is the third current i3, the electrical resistance Rz2 oscillates. The first current i1, the second current i2, and the third current i3 are oriented from the first magnetic layer 21 to the third magnetic layer 23.

[0253] In the fourth embodiment, for example, the characteristics described with reference to Figures 14(a) to 14(c) are obtained. When the current jc1 is the third current i3, a peak p1 is observed at a frequency fp1. This peak corresponds to the occurrence of high-frequency oscillation in the laminate 20S.

[0254] When the current jc1 is the first current i1 or the second current i2, the peak p1 is not clearly observed. At these currents, effective magnetization oscillation in the MAMR does not substantially occur.

[0255] In this manner, when the current jc1 flowing through the laminate 20S is the third current i3 between the first current i1 and the second current i2, the electrical resistance Rz2 of the laminate 20S oscillates.

[0256] In the fourth embodiment, a recording operation is performed using the stack 20S having such characteristics.

[0257] In a recording operation for recording information on a magnetic recording medium 80 using the magnetic head according to the fourth embodiment, the electric circuit 20D can supply the second current i2 to the stack 20S. By performing a recording operation in which the recording circuit 30D supplies a recording current Iw to the coil while supplying the second current i2 as described above, it is possible to increase the amount of the recording magnetic field directed from the first magnetic pole 31 to the magnetic recording medium 80, compared to a case in which the recording operation is performed without supplying the second current i2. The recording gap for good recording can be made smaller. According to the fourth embodiment, it is possible to provide a magnetic recording device capable of improving the recording density.

[0258] The magnetic recording device 210 includes a magnetic head according to the fourth embodiment (for example, the magnetic head 110B) and an electric circuit 20D capable of supplying a current jc1 (or a current Is) to the stack 20S. The current jc1 is oriented from the first magnetic layer 21 to the third magnetic layer 23. In a recording operation, the electric circuit 20D is capable of supplying the second current i2 to the stack 20S. The recording magnetic field output from the first magnetic pole 31 is effectively applied to the magnetic recording medium 80. A magnetic head capable of improving the recording density can be provided.

[0259] The fourth embodiment may include the following configurations (for example, technical solutions). (Configuration B1) A first magnetic pole; A second magnetic pole; a laminate provided between the first magnetic pole and the second magnetic pole; Equipped with The laminate comprises: A first magnetic layer; a second magnetic layer provided between the first magnetic pole and the first magnetic layer; a third magnetic layer provided between the first magnetic pole and the second magnetic layer; a first non-magnetic layer containing Cu and provided between the second magnetic layer and the first magnetic layer; a second nonmagnetic layer provided between the third magnetic layer and the second magnetic layer; a third nonmagnetic layer provided between the first magnetic pole and the third magnetic layer; Including, the second magnetic layer includes a first magnetic region and a second magnetic region, the second magnetic region being between the second nonmagnetic layer and the first magnetic region; the first magnetic region includes a first element including at least one of Fe, Co, and Ni; the second magnetic region includes the first element and a second element including at least one selected from the group consisting of Cr, V, Mn, Ti, and Sc; A magnetic head, wherein the first magnetic region does not contain the second element, or the concentration of the second element in the first magnetic region is lower than the concentration of the second element in the second magnetic region.

[0260] (Configuration B2) The concentration of the second element in the first magnetic region is equal to or greater than 0 atomic % and less than 20 atomic %, The magnetic head according to configuration B1, wherein the concentration of the second element in the second magnetic region is not less than 20 atomic % and not more than 50 atomic %.

[0261] (Configuration B3) The magnetic head of structure B1 or B2, wherein the first magnetic layer includes Fe and Co.

[0262] (Configuration B4) The magnetic head according to any one of structures B1 to B3, wherein the second nonmagnetic layer contains Cu.

[0263] (Structure B5) The magnetic head according to structure B4, wherein the second nonmagnetic layer contains the second element.

[0264] (Configuration B6) The magnetic head according to any one of structures B1 to B5, wherein the third nonmagnetic layer contains Cu.

[0265] (Configuration B7) The magnetic head according to any one of structures B1 to B6, wherein the third magnetic layer contains the first element and the second element.

[0266] (Configuration B8) The stack further includes a fourth magnetic layer, the fourth magnetic layer is between the first magnetic pole and the third nonmagnetic layer, the third magnetic layer contains the first element, A magnetic head according to any one of structures B1 to B6, wherein the third magnetic layer does not contain the second element, or the concentration of the second element in the third magnetic layer is lower than the concentration of the second element in the second magnetic region.

[0267] (Configuration B9) The stack further includes a fourth magnetic layer, the fourth magnetic layer is between the first magnetic pole and the third nonmagnetic layer, the fourth magnetic layer contains the first element and the second element, The magnetic head according to any one of structures B1 to B6, wherein the third magnetic layer contains the first element and the second element.

[0268] (Structure B10) the first magnetic region is in contact with the first nonmagnetic layer, The magnetic head according to any one of configurations B1 to B9, wherein the second magnetic region is in contact with the second nonmagnetic layer.

[0269] (Configuration B11) The magnetic head according to any one of configurations B1 to B10, wherein the first magnetic region has a thickness of not less than 0.5 nm and not more than 10 nm.

[0270] (Configuration B12) The magnetic head according to any one of configurations B1 to B11, wherein the second magnetic region has a thickness of 1 nm or more and 7 nm or less.

[0271] (Configuration B13) The magnetic head according to any one of structures B1 to B12, wherein the first magnetic layer has a thickness of 1 nm or more and 3 nm or less.

[0272] (Configuration B14) The magnetic head according to any one of structures B1 to B13, wherein the third magnetic layer has a thickness of 1 nm or more and 5 nm or less.

[0273] (Configuration B15) The magnetic head according to any one of structures B1 to B14, wherein the first nonmagnetic layer has a thickness of not less than 1 nm and not more than 5 nm.

[0274] (Configuration B16) The magnetic head according to any one of structures B1 to B15, wherein the second nonmagnetic layer has a thickness of not less than 1 nm and not more than 5 nm.

[0275] (Configuration B17) The magnetic head according to any one of structures B1 to B16, wherein the third nonmagnetic layer has a thickness of not less than 1 nm and not more than 5 nm.

[0276] (Configuration B18) The magnetic head according to any one of configurations B1 to B17, wherein the current flowing through the stack is oriented from the first magnetic layer to the third magnetic layer.

[0277] (Configuration B19) A magnetic head according to any one of configurations B1 to B17; an electric circuit capable of supplying a current to the laminate; Preparation, The current has a direction from the first magnetic layer to the third magnetic layer.

[0278] (Configuration B20) Further comprising a magnetic recording medium; an electrical resistance of the laminate when the current flowing through the laminate is a first current is a first resistance; when the current flowing through the stack is a second current greater than the first current, the electrical resistance of the stack is a second resistance greater than the first resistance, when the current flowing through the stack is a third current between the first current and the second current, the electrical resistance of the stack oscillates; The magnetic recording device according to structure B19, wherein, in a recording operation for recording information on the magnetic recording medium using the magnetic head, the electric circuit is capable of supplying the second current to the stack.

[0279] In the magnetic heads according to the fourth embodiment (magnetic heads 110B, 111B, and 112B), the second magnetic region 22b (for example, a magnetic region having negative spin polarization) and the third magnetic layer 23 (for example, a magnetic layer having negative spin polarization) are made of (Fe 100-x Co x ) 100-y E y (10 atm%≦x≦50 atm%, 10 atm%≦y≦90 atm%). The second element E includes at least one selected from the group consisting of Cr, V, Mn, Ti, and Sc. The composition ratio x and the composition ratio y are atomic percent (atm%). This makes it easy to obtain, for example, a high saturation magnetic flux density and a negative spin polarization with a large absolute value. Efficient magnetization reversal is obtained. The recording density can be improved.

[0280] Fifth embodiment FIG. 29 is a schematic cross-sectional view illustrating a part of the magnetic recording device according to the fifth embodiment. 29, in a magnetic head 111C of a magnetic recording device 210 according to the fifth embodiment, the stack 20 further includes a third magnetic layer 23 and a fourth nonmagnetic layer 44 in addition to the first magnetic layer 21, the second magnetic layer 22, the first nonmagnetic layer 41, the second nonmagnetic layer 42 and the third nonmagnetic layer 43. The rest of the configuration of the magnetic head 111C is similar to that of the magnetic head according to the second or third embodiment. An example of the magnetic head 111C will be described below.

[0281] 29, the third magnetic layer 23 is provided between the first non-magnetic layer 41 and the first magnetic layer 21. The fourth non-magnetic layer 44 is provided between the third magnetic layer 23 and the first magnetic layer 21. The third magnetic layer 23 includes a first element including at least one of Fe, Co, and Ni, and a second element including at least one selected from the group consisting of Cr, V, Mn, Ti, and Sc. The third magnetic layer 23 has, for example, negative polarization.

[0282] The first magnetic layer 21 and the second magnetic layer 22 include at least one of Fe, Co, and Ni, for example. For example, they include a magnetic material having positive polarization. For example, the first magnetic layer 21 and the second magnetic layer 22 do not include the second element. Alternatively, the concentration of the second element included in the first magnetic layer 21 and the second magnetic layer 22 is lower than the concentration of the second element included in the third magnetic layer 23.

[0283] In the magnetic head 111C, for example, the first nonmagnetic layer 41 includes at least one selected from the group consisting of Cu, Ag, Au, Al, and Cr. The first nonmagnetic layer 41 functions as, for example, a layer that propagates polarized spins.

[0284] In the magnetic head 111C, for example, the second nonmagnetic layer 42 includes at least one selected from the group consisting of Cu, Ag, Au, Al, and Cr. The second nonmagnetic layer 42 functions as a layer that propagates polarized spins, for example.

[0285] In the magnetic head 111C, for example, the third nonmagnetic layer 43 includes at least one selected from the group consisting of Ta, Pt, W, Mo, Ir, Ru, Tb, Rh, Cr, and Pd. The third nonmagnetic layer 43 functions as a layer that attenuates polarized spins, for example.

[0286] In the magnetic head 111C, for example, the fourth nonmagnetic layer 44 includes at least one selected from the group consisting of Ta, Pt, W, Mo, Ir, Ru, Tb, Rh, Cr, and Pd. The fourth nonmagnetic layer 44 functions as a layer that attenuates polarized spins, for example.

[0287] With such a configuration, the magnetic head 111C can obtain a higher gain.

[0288] For example, there is a first reference example in which the third magnetic layer 23 is not provided in the configuration of the magnetic head 111C. In the first reference example, the laminate 20 includes a first magnetic layer 21, a second magnetic layer 22, a first non-magnetic layer 41, a second non-magnetic layer 42, and a third non-magnetic layer 43. The second magnetic layer 22 is provided between the first magnetic pole 31 and the first magnetic layer 21. The first non-magnetic layer 41 is provided between the second magnetic layer 22 and the first magnetic layer 21. The second non-magnetic layer 42 is provided between the first magnetic layer 21 and the second magnetic pole 32. The third non-magnetic layer 43 is provided between the first magnetic pole 31 and the second magnetic layer 22. The second non-magnetic layer 42 includes at least one selected from the group consisting of Cu, Ag, Au, Al, and Cr. The third nonmagnetic layer 43 includes at least one selected from the group consisting of Ta, Pt, W, Mo, Ir, Ru, Tb, Rh, Cr, and Pd. The first nonmagnetic layer 41 includes at least one selected from the group consisting of Cu, Ag, Au, Al, and Cr.

[0289] FIG. 30 is a schematic view illustrating the characteristics of the magnetic recording device according to the fifth embodiment. FIG. 30 illustrates a simulation result of the characteristics of the magnetic head 111C according to the fifth embodiment. The simulation result of the response of the magnetization of the first magnetic layer 21, the second magnetic layer 22, and the third magnetic layer 23 combined when the recording current Iw is reversed while the second current i2 is supplied to the stack 20 is illustrated. In FIG. 30, the horizontal axis is time tm. The polarity of the recording current Iw reverses at the first time tm1 and the second time tm2. In FIG. 30, the vertical axis is a parameter P1 corresponding to the amount of reversal of the magnetization. When the parameter P1 is negative, the gain increases based on the time when no current is supplied to the stack 20.

[0290] 30, in the magnetic head 111C, the parameter P1 is negative immediately after the polarity of the recording magnetic field is reversed (the first time tm1 or the second time tm2), and becomes positive as time passes. In the magnetic head 111C, when the frequency of the recording magnetic field is high and the time tm after the polarity reversal is short, an increase in gain is obtained.

[0291] As shown in Fig. 30, in the magnetic head 111C, the time tm at which the maximum absolute value of the parameter P1 is obtained is 0.45 ns. On the other hand, in the above-mentioned first reference example, the time tm at which the maximum absolute value of the parameter P1 is obtained is 0.4 ns. The magnetization in the first magnetic pole 31 reverses a little after the time (the first time tm1 or the second time tm2) at which the polarity of the recording magnetic field reverses. The reversal time of the magnetization of the first magnetic layer 21 in the magnetic head 111C more closely matches the reversal time of the magnetization in the first magnetic pole 31. This provides a greater gain.

[0292] A second reference example may be considered in which the first magnetic layer 21 is provided, and the second magnetic layer 22 and the third nonmagnetic layer 43 are not provided. In the second reference example, the first nonmagnetic layer 41 contacts the first magnetic pole 31.

[0293] FIG. 31 is a schematic diagram illustrating the characteristics of a magnetic recording device. Fig. 31 illustrates the relationship between the frequency of the recording magnetic field and the gain for the magnetic head 118 of the first reference example, the magnetic head 119 of the second reference example, and the magnetic head 111C. The horizontal axis of Fig. 31 is the frequency fw of the recording magnetic field. The frequency fw corresponds to the frequency of the recording current Iw. The vertical axis of Fig. 31 is the gain Gn0 based on the case when no current is supplied to the stack 20.

[0294] 31, in the magnetic head 111C, a high gain Gn0 can be obtained even at a low frequency fw, compared with the magnetic head 118 of the first reference example. In the fifth embodiment, too, a high recording capability can be obtained during high-speed recording operation at a high frequency. The recording density can be improved more effectively.

[0295] 32(a) to 32(c) are schematic cross-sectional views illustrating the characteristics of the magnetic recording device according to the fifth embodiment. These figures show an example of a change in the direction of magnetization in the magnetic head 111 C. As shown in these figures, the magnetization 23M of the third magnetic layer 23 moves in conjunction with the magnetization 22M of the second magnetic layer 22, for example.

[0296] Sixth embodiment FIG. 33 is a schematic cross-sectional view illustrating a part of the magnetic recording device according to the sixth embodiment. As shown in FIG. 33, in the magnetic head 121C of the magnetic recording device 210 of the sixth embodiment, the stack 20 further includes, in addition to the first magnetic layer 21, the second magnetic layer 22, the first non-magnetic layer 41, the second non-magnetic layer 42 and the third non-magnetic layer 43, a third magnetic layer 23 and a fourth non-magnetic layer 44.

[0297] In the magnetic head 121C, the third magnetic layer 23 is provided between the first non-magnetic layer 41 and the first magnetic layer 21. The fourth non-magnetic layer 44 is provided between the third magnetic layer 23 and the first magnetic layer 21. The third magnetic layer 23 includes a first element including at least one of Fe, Co, and Ni, and a second element including at least one selected from the group consisting of Cr, V, Mn, Ti, and Sc.

[0298] The first nonmagnetic layer 41 includes at least one selected from the group consisting of Cu, Ag, Au, Al, and Cr. The second nonmagnetic layer 42 includes at least one selected from the group consisting of Cu, Ag, Au, Al, and Cr. The third nonmagnetic layer 43 includes at least one selected from the group consisting of Ta, Pt, W, Mo, Ir, Ru, Tb, Rh, Cr, and Pd. The fourth nonmagnetic layer 44 includes at least one selected from the group consisting of Ta, Pt, W, Mo, Ir, Ru, Tb, Rh, Cr, and Pd.

[0299] The magnetic head 121C having such a configuration also provides a higher gain.

[0300] In the magnetic heads 111C and 121C, the third magnetic layer 23 has a thickness of, for example, 1 nm or more and 5 nm or less. The fourth non-magnetic layer 44 has a thickness of, for example, 1 nm or more and 5 nm or less. These thicknesses are lengths along the first direction D1. As already described, the first direction D1 may be inclined with respect to the X-axis direction.

[0301] According to the fifth and sixth embodiments, it is possible to provide a magnetic recording device capable of improving the recording density.

[0302] The fifth and sixth embodiments may include the following configurations (for example, technical solutions). (Configuration C1) A magnetic head; A magnetic recording medium; An electric circuit; Equipped with The magnetic head includes: A first magnetic pole; A second magnetic pole; a laminate provided between the first magnetic pole and the second magnetic pole; Including, The laminate comprises: A first magnetic layer; a second magnetic layer provided between the first magnetic pole and the first magnetic layer; a first nonmagnetic layer provided between the second magnetic layer and the first magnetic layer; a second nonmagnetic layer provided between the first magnetic layer and the second magnetic pole; a third nonmagnetic layer provided between the first magnetic pole and the second magnetic layer; Including, the second nonmagnetic layer includes at least one selected from the group consisting of Cu, Ag, Au, Al, and Cr; the third nonmagnetic layer includes at least one selected from the group consisting of Ta, Pt, W, Mo, Ir, Ru, Tb, Rh, Cr, and Pd; an electrical resistance of the laminate when a current flowing through the laminate is a first current is a first resistance; when the current flowing through the stack is a second current greater than the first current, the electrical resistance of the stack is a second resistance greater than the first resistance, when the current flowing through the stack is a third current between the first current and the second current, the electrical resistance of the stack oscillates; A magnetic recording device, wherein the electric circuit is capable of supplying the second current to the stack during a recording operation for recording information on the magnetic recording medium using the magnetic head.

[0303] (Configuration C2) A magnetic head; A magnetic recording medium; An electric circuit; Equipped with The magnetic head includes: A first magnetic pole; A second magnetic pole; a laminate provided between the first magnetic pole and the second magnetic pole; Including, The laminate comprises: A first magnetic layer; a second magnetic layer provided between the first magnetic layer and the second magnetic pole; a first nonmagnetic layer provided between the first magnetic layer and the second magnetic layer; a second nonmagnetic layer provided between the first magnetic pole and the first magnetic layer; a third nonmagnetic layer provided between the second magnetic layer and the second magnetic pole; Including, the second nonmagnetic layer includes at least one selected from the group consisting of Cu, Ag, Au, Al, and Cr; the third nonmagnetic layer includes at least one selected from the group consisting of Ta, Pt, W, Mo, Ir, Ru, Tb, Rh, Cr, and Pd; an electrical resistance of the laminate when a current flowing through the laminate is a first current is a first resistance; when the current flowing through the stack is a second current greater than the first current, the electrical resistance of the stack is a second resistance greater than the first resistance, when the current flowing through the stack is a third current between the first current and the second current, the electrical resistance of the stack oscillates; A magnetic recording device, wherein the electric circuit is capable of supplying the second current to the stack during a recording operation for recording information on the magnetic recording medium using the magnetic head.

[0304] (Configuration C3) the first nonmagnetic layer includes a first material or a second material; The first material includes at least one selected from the group consisting of Cu, Ag, Au, Al, and Cr; The magnetic recording device of structure C1 or C2, wherein the second material includes at least one selected from the group consisting of Ta, Pt, W, Mo, Ir, Ru, Tb, Rh, and Pd.

[0305] (Configuration C4) The laminate comprises: a third magnetic layer provided between the first nonmagnetic layer and the first magnetic layer; a fourth nonmagnetic layer provided between the third magnetic layer and the first magnetic layer; Further comprising: the third magnetic layer includes a first element including at least one of Fe, Co, and Ni, and a second element including at least one selected from the group consisting of Cr, V, Mn, Ti, and Sc; the first nonmagnetic layer includes at least one selected from the group consisting of Cu, Ag, Au, Al, and Cr; The magnetic recording device according to structure C1 or C2, wherein the fourth nonmagnetic layer includes at least one selected from the group consisting of Ta, Pt, W, Mo, Ir, Ru, Tb, Rh, Cr, and Pd.

[0306] (Configuration C5) The magnetic recording device according to any one of configurations C1 to C4, wherein the second current has a direction from the first magnetic layer to the second magnetic layer.

[0307] (Configuration C6) The magnetic recording device according to any one of configurations C1 to C5, wherein the second nonmagnetic layer has a thickness of 1 nm or more and 5 nm or less.

[0308] (Configuration C7) The magnetic recording device according to any one of configurations C1 to C6, wherein the third nonmagnetic layer has a thickness of not less than 2 nm and not more than 6 nm.

[0309] (Configuration C8) The magnetic recording device according to any one of configurations C1 to C7, wherein the first magnetic layer and the second magnetic layer contain at least one of Fe and Co.

[0310] (Configuration C9) The magnetic recording device according to any one of configurations C1 to C8, wherein the first magnetic layer has a thickness of not less than 2 nm and not more than 8 nm.

[0311] (Configuration C10) The magnetic recording device according to any one of configurations C1 to C9, wherein the second magnetic layer has a thickness of not less than 2 nm and not more than 4 nm.

[0312] (Configuration C11) during the recording operation when the recording current corresponding to the information has a first frequency, when the electric circuit does not supply the second current to the stack, the intensity of a signal recorded on the magnetic recording medium is a first intensity; in the recording operation when the recording current has the first frequency, when the electric circuit supplies the second current to the stack, a signal recorded on the magnetic recording medium has a second intensity; in the recording operation when the recording current corresponding to the information has a second frequency higher than the first frequency, when the electric circuit does not supply the second current to the stack, the intensity of the signal recorded on the magnetic recording medium is a third intensity; in the recording operation when the recording current has the second frequency, when the electric circuit supplies the second current to the stack, the intensity of the signal recorded on the magnetic recording medium is a fourth intensity; The magnetic recording device according to any one of configurations C1 to C10, wherein a second ratio of the fourth intensity to the third intensity is higher than a first ratio of the second intensity to the first intensity.

[0313] In the magnetic heads according to the fifth and sixth embodiments (magnetic heads 111C and 121C), the third magnetic layer 23 (for example, a magnetic layer having negative spin polarization) is (Fe 100-x Co x ) 100-y E y(10 atm%≦x≦50 atm%, 10 atm%≦y≦90 atm%). The second element E includes at least one selected from the group consisting of Cr, V, Mn, Ti, and Sc. The composition ratio x and the composition ratio y are atomic percent (atm%). This makes it easy to obtain, for example, a high saturation magnetic flux density and a negative spin polarization with a large absolute value. Efficient magnetization reversal is obtained. The recording density can be improved.

[0314] In the first to sixth embodiments, the first magnetic pole 31 may include a plurality of magnetic regions aligned along the X-axis direction. The second magnetic pole 32 may include a plurality of magnetic regions aligned along the X-axis direction. The boundaries between the plurality of magnetic regions may be clear or unclear. For example, the plurality of magnetic regions are continuous.

[0315] Below, examples of the magnetic head and the magnetic recording medium 80 included in the magnetic recording device 210 according to the first to sixth embodiments will be described. FIG. 34 is a schematic cross-sectional view illustrating the magnetic head according to the embodiment. As shown in FIG. 34, in a magnetic head according to an embodiment (e.g., magnetic head 110), a first direction D1 from the first magnetic pole 31 to the second magnetic pole 32 may be inclined with respect to the X-axis direction. The first direction D1 corresponds to the stacking direction of the stacked body 20. The X-axis direction is along the medium facing surface 30F. The angle between the first direction D1 and the medium facing surface 30F is defined as angle θ1. The angle θ1 is, for example, not less than 15 degrees and not more than 30 degrees. The angle θ1 may be 0 degrees.

[0316] When the first direction D1 is inclined with respect to the X-axis direction, the thickness of the layer corresponds to the length along the first direction D1. The configuration in which the first direction D1 is inclined with respect to the X-axis direction may be applied to any magnetic head according to the embodiment. For example, the interface between the first magnetic pole 31 and the laminate 20 and the interface between the laminate 20 and the second magnetic pole 32 may be inclined with respect to the X-axis direction.

[0317] FIG. 35 is a schematic perspective view illustrating the magnetic recording device according to the embodiment. 35, a magnetic head according to an embodiment (e.g., magnetic head 110) is used together with a magnetic recording medium 80. In this example, the magnetic head 110 includes a recording unit 60 and a reproducing unit 70. The recording unit 60 of the magnetic head 110 records information on the magnetic recording medium 80. The reproducing unit 70 reproduces the information recorded on the magnetic recording medium 80.

[0318] The magnetic recording medium 80 includes, for example, a medium substrate 82 and a magnetic recording layer 81 provided on the medium substrate 82. Magnetization 83 of the magnetic recording layer 81 is controlled by the recording section 60. For example, perpendicular magnetic recording is performed.

[0319] The reproducing unit 70 includes, for example, a first reproducing magnetic shield 72a, a second reproducing magnetic shield 72b, and a magnetic reproducing element 71. The magnetic reproducing element 71 is provided between the first reproducing magnetic shield 72a and the second reproducing magnetic shield 72b. The magnetic reproducing element 71 can output a signal corresponding to the magnetization 83 of the magnetic recording layer 81.

[0320] 35, the magnetic recording medium 80 moves relative to the magnetic head 110 in a medium movement direction 85. The magnetic head 110 controls information corresponding to the magnetization 83 of the magnetic recording layer 81 at an arbitrary position. The magnetic head 110 reproduces information corresponding to the magnetization 83 of the magnetic recording layer 81 at an arbitrary position.

[0321] FIG. 36 is a schematic perspective view illustrating a part of the magnetic recording device according to the embodiment. FIG. 36 illustrates a head slider. The magnetic head 110 is mounted on a head slider 159. The head slider 159 is made of, for example, Al 2 O 3 / TiC, etc. The head slider 159 moves relative to the magnetic recording medium while floating above or in contact with the magnetic recording medium.

[0322] The head slider 159 includes, for example, an air inflow side 159A and an air outflow side 159B. The magnetic head 110 is provided on a side surface of the air outflow side 159B of the head slider 159. This allows the magnetic head 110 to move relative to the magnetic recording medium while floating above or in contact with the magnetic recording medium.

[0323] FIG. 37 is a schematic perspective view illustrating the magnetic recording device according to the embodiment. As shown in FIG. 37, a rotary actuator is used in the magnetic recording device 150 according to the embodiment. The recording medium disk 180 is mounted on a spindle motor 180M. The recording medium disk 180 is rotated in the direction of the arrow AR by the spindle motor 180M. The spindle motor 180M responds to a control signal from a drive control unit. The magnetic recording device 150 according to the embodiment may include a plurality of recording medium disks 180. The magnetic recording device 150 may include a recording medium 181. The recording medium 181 is, for example, an SSD (Solid State Drive). For the recording medium 181, for example, a non-volatile memory such as a flash memory is used. For example, the magnetic recording device 150 may be a hybrid HDD (Hard Disk Drive).

[0324] The head slider 159 records and reproduces information to be recorded on the recording medium disk 180. The head slider 159 is provided at the tip of the thin-film suspension 154. Near the tip of the head slider 159, a magnetic head according to the embodiment is provided.

[0325] When the recording medium disk 180 rotates, the pressing pressure by the suspension 154 and the pressure generated at the medium facing surface (ABS) of the head slider 159 are balanced. The distance between the medium facing surface of the head slider 159 and the surface of the recording medium disk 180 is a predetermined flying height. In an embodiment, the head slider 159 may be in contact with the recording medium disk 180. For example, a contact running type may be applied.

[0326] The suspension 154 is connected to one end of an arm 155 (e.g., an actuator arm). The arm 155 has, for example, a bobbin portion. The bobbin portion holds a drive coil. A voice coil motor 156 is provided at the other end of the arm 155. The voice coil motor 156 is a type of linear motor. The voice coil motor 156 includes, for example, a drive coil and a magnetic circuit. The drive coil is wound around the bobbin portion of the arm 155. The magnetic circuit includes a permanent magnet and an opposing yoke. The drive coil is provided between the permanent magnet and the opposing yoke. The suspension 154 has one end and the other end. The magnetic head is provided at one end of the suspension 154. The arm 155 is connected to the other end of the suspension 154.

[0327] Arm 155 is held by a ball bearing. The ball bearings are provided at two locations, above and below bearing portion 157. Arm 155 can rotate and slide by voice coil motor 156. The magnetic head can be moved to any position on recording medium disk 180.

[0328] 38A and 38B are schematic perspective views illustrating a part of the magnetic recording device according to the embodiment. Fig. 38(a) illustrates a partial configuration of the magnetic recording device, and is an enlarged perspective view of a head stack assembly 160. Fig. 38(b) is a perspective view illustrating a magnetic head assembly (head gimbal assembly: HGA) 158 which is a part of the head stack assembly 160.

[0329] 38(a), the head stack assembly 160 includes a bearing portion 157, a head gimbal assembly 158, and a support frame 161. The head gimbal assembly 158 extends from the bearing portion 157. The support frame 161 extends from the bearing portion 157. The extension direction of the support frame 161 is opposite to the extension direction of the head gimbal assembly 158. The support frame 161 supports a coil 162 of the voice coil motor 156.

[0330] As shown in FIG. 38( b ), the head gimbal assembly 158 has an arm 155 extending from a bearing portion 157 , and a suspension 154 extending from the arm 155 .

[0331] A head slider 159 is provided at the tip of the suspension 154. The head slider 159 is provided with a magnetic head according to the embodiment.

[0332] A magnetic head assembly (head gimbal assembly) 158 according to the embodiment includes a magnetic head according to the embodiment, a head slider 159 provided with the magnetic head, a suspension 154, and an arm 155. The head slider 159 is provided at one end of the suspension 154. The arm 155 is connected to the other end of the suspension 154.

[0333] The suspension 154 has, for example, lead wires (not shown) for recording and reproducing signals. The suspension 154 may have, for example, lead wires (not shown) for a heater for adjusting the flying height. The suspension 154 may have, for example, lead wires (not shown) for a spin transfer torque oscillator or the like. These lead wires are electrically connected to a plurality of electrodes provided on the magnetic head.

[0334] A signal processing unit 190 is provided in the magnetic recording device 150. The signal processing unit 190 uses a magnetic head to record and reproduce signals on a magnetic recording medium. The input / output lines of the signal processing unit 190 are connected to, for example, electrode pads of the head gimbal assembly 158, and are electrically connected to the magnetic head.

[0335] The magnetic recording device 150 according to the embodiment includes a magnetic recording medium, a magnetic head according to the embodiment, a movable unit, a position control unit, and a signal processing unit. The movable unit allows the magnetic recording medium and the magnetic head to be relatively moved while being separated from each other or in contact with each other. The position control unit aligns the magnetic head with a predetermined recording position on the magnetic recording medium. The signal processing unit records and reproduces signals on the magnetic recording medium using the magnetic head.

[0336] For example, the magnetic recording medium is a recording medium disk 180. The movable portion includes, for example, a head slider 159. The position control portion includes, for example, a head gimbal assembly 158.

[0337] According to the embodiment, it is possible to provide a magnetic head and a magnetic recording device that enable improvement in recording density.

[0338] In this specification, "vertical" and "parallel" do not only mean strictly vertical and strictly parallel, but also include, for example, variations in the manufacturing process, and may mean substantially vertical and substantially parallel.

[0339] The above describes the embodiments of the present invention with reference to specific examples. However, the present invention is not limited to these specific examples. For example, the specific configurations of each element included in the magnetic head, such as the magnetic pole, the laminate, the magnetic layer, the non-magnetic layer, and the wiring, are included in the scope of the present invention as long as a person skilled in the art can implement the present invention in a similar manner and obtain the same effects by appropriately selecting from the known range.

[0340] Any combination of two or more elements of each embodiment, within the scope of technical feasibility, is also included within the scope of the present invention as long as it includes the gist of the present invention.

[0341] In addition, all magnetic heads and magnetic recording devices that can be implemented by a person skilled in the art by making appropriate design modifications based on the magnetic head and magnetic recording device described above as embodiments of the present invention also fall within the scope of the present invention as long as they include the gist of the present invention.

[0342] In addition, within the scope of the concept of the present invention, a person skilled in the art may conceive of various modifications and alterations, and it will be understood that these modifications and alterations also fall within the scope of the present invention.

[0343] Although some embodiments of the present invention have been described, these embodiments are presented as examples and are not intended to limit the scope of the invention. These novel embodiments can be implemented in various other forms, and various omissions, substitutions, and modifications can be made without departing from the spirit of the invention. These embodiments and their modifications are included in the scope and spirit of the invention, and are included in the scope of the invention and its equivalents described in the claims. [Explanation of symbols]

[0344] 20...Laminate, 20D...Electric circuit, 21...First magnetic layer, 21a, 21b...First and second magnetic regions, 22...Second magnetic layer, 22c, 22d...Third and fourth magnetic regions, 23...Third magnetic layer, 30D...Recording circuit, 30F...Medium facing surface, 30c...Coil, 30i...Insulating portion, 31, 32...First and second magnetic poles, 33...Shield, 41-43...First to third non-magnetic layers, 60...Recording portion, 70...Reading portion, 71...Magnetic reading element, 72a, 72b...First and second read magnetic shields, 80...Magnetic recording medium, 81...Magnetic recording layer, 82...Medium substrate, 83...Magnetization, 85...Medium movement direction, θ1...Angle, 110, 111, 112...Magnetic head, 150...magnetic recording device, 154...suspension, 155...arm, 156...voice coil motor, 157...bearing portion, 158...head gimbal assembly, 159...head slider, 159A...air inflow side, 159B...air outflow side, 160...head stack assembly, 161...support frame, 162...coil, 180...recording medium disk, 180M...spindle motor, 181...recording medium, 190...signal processing portion, 210...magnetic recording device, AR, AR1...arrow, D1...first direction, I1 to I3...first to third currents, Ith...threshold current, Iw...recording current, Mz, Mz1, Mz2...magnetization, OS...oscillation strength, RR1...thickness ratio, Rx...electrical resistance, Rx1 to Rx3...first to third resistances, T1, T2...first and second terminals, W1, W2...first and second wiring, ic, jc1...current, je, je1...electron current, t1~t3...first to third thicknesses, t41~t43...thickness, tm...time, tm1, tm2...first and second times, ts...sum

Claims

1. A first magnetic pole; A second magnetic pole; a laminate provided between the first magnetic pole and the second magnetic pole; Equipped with The laminate comprises: A first magnetic layer; a second magnetic layer provided between the first magnetic layer and the second magnetic pole; a first nonmagnetic layer provided between the first magnetic layer and the second magnetic layer; a second nonmagnetic layer provided between the second magnetic layer and the second magnetic pole; a third nonmagnetic layer provided between the first magnetic pole and the first magnetic layer; Including, the first magnetic layer includes a first element including at least one of Fe, Co, and Ni; The second magnetic layer is made of (Fe １００－ｘ Co ｘ ) １００－ｙ E ｙ (10 atm%≦x≦50 atm%, 10 atm%≦y≦90 atm%), the second element E includes at least one selected from the group consisting of Cr, V, Mn, Ti, and Sc, the first magnetic layer does not contain the second element, or the concentration of the second element in the first magnetic layer is lower than the concentration of the second element in the second magnetic layer; A magnetic head, wherein the composition ratio x is 25 atm % or more and 35 atm % or less.

2. 2. The magnetic head according to claim 1, wherein the composition ratio y is equal to or greater than 10 atm % and equal to or less than 30 atm %.

3. 3. The magnetic head of claim 1, wherein a first thickness of the first magnetic layer along a first direction from the first magnetic pole to the second magnetic pole is 0.25 to 4 times a second thickness of the second magnetic layer along the first direction.

4. The magnetic head of claim 3 , wherein the first thickness is greater than or equal to 0.33 times the second thickness.

5. 5. The magnetic head according to claim 3, wherein the third nonmagnetic layer is in contact with the first magnetic pole and the first magnetic layer.

6. 6. The magnetic head according to claim 3, wherein the second nonmagnetic layer is in contact with the second magnetic layer and the second magnetic pole.

7. A first magnetic pole; A second magnetic pole; a laminate provided between the first magnetic pole and the second magnetic pole; Equipped with The laminate comprises: A first magnetic layer; a second magnetic layer provided between the first magnetic layer and the second magnetic pole; a first nonmagnetic layer provided between the first magnetic layer and the second magnetic layer; a second nonmagnetic layer provided between the second magnetic layer and the second magnetic pole; a third nonmagnetic layer provided between the first magnetic pole and the first magnetic layer; Including, the first magnetic layer includes a first element including at least one of Fe, Co, and Ni; The second magnetic layer is made of (Fe １００－ｘ Co ｘ ) １００－ｙ E ｙ (10 atm%≦x≦50 atm%, 10 atm%≦y≦90 atm%), the second element E includes at least one selected from the group consisting of Cr, V, Mn, Ti, and Sc, the first magnetic layer does not contain the second element, or the concentration of the second element in the first magnetic layer is lower than the concentration of the second element in the second magnetic layer; a first thickness of the first magnetic layer along a first direction from the first magnetic pole to the second magnetic pole is 0.25 to 4 times a second thickness of the second magnetic layer along the first direction; the second nonmagnetic layer is in contact with the second magnetic layer and the second magnetic pole.

8. 8. The magnetic head according to claim 3, wherein the sum of the first thickness and the second thickness is 15 nm or more.

9. The stack further includes a third magnetic layer, the third magnetic layer is provided between the second magnetic layer and the second nonmagnetic layer, the third magnetic layer includes a first element including at least one of Fe, Co, and Ni; A magnetic head described in any one of claims 3 to 8, wherein the third magnetic layer does not contain the second element, or the concentration of the second element in the third magnetic layer is lower than the concentration of the second element in the second magnetic layer.

10. Further comprising a coil; a recording magnetic field generated from at least one of the first magnetic pole and the second magnetic pole changes in response to a recording current flowing through the coil; an electrical resistance of the laminate is a first resistance when the recording current is a first current; the electrical resistance is a second resistance when the recording current is a second current, the electrical resistance is a third resistance when the recording current is a third current, an absolute value of the first current is smaller than an absolute value of the second current and smaller than an absolute value of the third current; a direction of the second current is opposite to a direction of the third current, 10. The magnetic head according to claim 3, wherein the first resistance is lower than the second resistance and lower than the third resistance.

11. A first magnetic pole; A second magnetic pole; a laminate provided between the first magnetic pole and the second magnetic pole; Including, The laminate comprises: A first magnetic layer; a second magnetic layer provided between the first magnetic pole and the first magnetic layer; a third magnetic layer provided between the first magnetic pole and the second magnetic layer; a first non-magnetic layer provided between the first magnetic layer and the second magnetic pole; a second nonmagnetic layer provided between the second magnetic layer and the first magnetic layer; a third nonmagnetic layer provided between the third magnetic layer and the second magnetic layer; Including, the first magnetic layer includes at least one of Fe, Co, and Ni; the second magnetic layer includes at least one of Fe, Co, and Ni; The third magnetic layer is made of (Fe １００－ｘ Co ｘ ) １００－ｙ E ｙ (10 atm%≦x≦50 atm%, 10 atm%≦y≦90 atm%), the second element E includes at least one selected from the group consisting of Cr, V, Mn, Ti, and Sc, the first magnetic layer and the second magnetic layer do not contain the second element, or the concentration of the second element in the first magnetic layer and the second magnetic layer is lower than the concentration of the second element in the third magnetic layer; the first nonmagnetic layer includes at least one selected from the group consisting of Cu, Ag, Au, Al, and Cr; the second nonmagnetic layer includes at least one selected from the group consisting of Ta, Pt, W, Mo, Ir, Ru, Tb, Rh, Cr, and Pd; The magnetic head, wherein the third nonmagnetic layer includes at least one selected from the group consisting of Cu, Ag, Au, Al, and Cr.

12. A first magnetic pole; A second magnetic pole; a laminate provided between the first magnetic pole and the second magnetic pole; Including, The laminate comprises: A first magnetic layer; a second magnetic layer provided between the first magnetic pole and the first magnetic layer; a third magnetic layer provided between the first magnetic pole and the second magnetic layer; a first non-magnetic layer provided between the first magnetic layer and the second magnetic pole; a second nonmagnetic layer provided between the second magnetic layer and the first magnetic layer; a third nonmagnetic layer provided between the third magnetic layer and the second magnetic layer; Including, The first magnetic layer is made of (Fe １００－ｘ Co ｘ ) １００－ｙ E ｙ (10 atm%≦x≦50 atm%, 10 atm%≦y≦90 atm%), the second element E includes at least one selected from the group consisting of Cr, V, Mn, Ti, and Sc, the second magnetic layer includes at least one of Fe, Co, and Ni, and the second magnetic layer does not include the second element, or the concentration of the second element in the second magnetic layer is lower than the concentration of the second element in the first magnetic layer; The third magnetic layer is made of (Fe １００－ｘ Co ｘ ) １００－ｙ EX ｙ (10 atm%≦x≦50 atm%, 10 atm%≦y≦90 atm%), and the fourth element EX includes at least one selected from the group consisting of Cr, V, Mn, Ti, and Sc, the second magnetic layer does not contain the fourth element, or the concentration of the fourth element in the second magnetic layer is lower than the concentration of the fourth element in the third magnetic layer; the first nonmagnetic layer includes at least one selected from the group consisting of Cu, Ag, Au, Al, and Cr; the second nonmagnetic layer includes at least one selected from the group consisting of Cu, Ag, Au, Al, and Cr; The magnetic head, wherein the third nonmagnetic layer includes at least one selected from the group consisting of Cu, Ag, Au, Al, and Cr.

13. A first magnetic pole; A second magnetic pole; a laminate provided between the first magnetic pole and the second magnetic pole; Equipped with The laminate comprises: A first magnetic layer; a second magnetic layer provided between the first magnetic pole and the first magnetic layer; a third magnetic layer provided between the first magnetic pole and the second magnetic layer; a first non-magnetic layer containing Cu and provided between the second magnetic layer and the first magnetic layer; a second nonmagnetic layer provided between the third magnetic layer and the second magnetic layer; a third nonmagnetic layer provided between the first magnetic pole and the third magnetic layer; Including, the second magnetic layer includes a first magnetic region and a second magnetic region, the second magnetic region being between the second nonmagnetic layer and the first magnetic region; The first magnetic region includes a first element including at least one of Fe, Co, and Ni; The second magnetic region is made of (Fe １００－ｘ Co ｘ ) １００－ｙ E ｙ (10 atm%≦x≦50 atm%, 10 atm%≦y≦90 atm%), the second element E includes at least one selected from the group consisting of Cr, V, Mn, Ti, and Sc, A magnetic head, wherein the first magnetic region does not contain the second element, or the concentration of the second element in the first magnetic region is lower than the concentration of the second element in the second magnetic region.

14. A magnetic head according to any one of claims 1 to 13, An electric circuit; Equipped with The electric circuit is capable of supplying an electric current to the laminate; The current has a direction from the first magnetic layer to the second magnetic layer.

15. A magnetic head according to any one of claims 1 to 13, A magnetic recording medium; Equipped with A magnetic recording device in which information is recorded on the magnetic recording medium by the magnetic head.

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