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 an embodiment, a magnetic head includes a first magnetic pole, a second magnetic pole, and a laminated body. The first magnetic pole includes a first surface and a second surface intersecting the first surface. The second surface includes a first surface region. The second magnetic pole includes a third surface and a fourth surface intersecting the third surface. The fourth surface includes a second surface region. A direction from the first surface region to the second surface region is along a first direction. The first surface region and the second surface region are along a second direction and a third direction. The first surface and the third surface are along the third direction. The laminated body is provided between the first surface region and the second surface region. The laminated body includes a first magnetic layer and a second magnetic layer. The second magnetic layer includes a second magnetic layer surface opposite to the second surface region. A width ratio of a second width along the third direction of the second magnetic layer surface to a first width along the third direction of the first surface area is 0.25 or more and 0.92 or less.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] FIELD An embodiment of the present invention relates to a magnetic head and a magnetic recording device. [Background technology]

[0002] 2. Description of the Related Art Magnetic heads are used to record information on magnetic recording media such as HDDs (Hard Disk Drives), etc. It is desirable to improve the recording density of magnetic heads and magnetic recording devices. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Laid-Open No. 2008-277586 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 an 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. The first magnetic pole includes a first surface and a second surface intersecting the first surface. The second surface includes a first surface region continuous with the first surface. The second magnetic pole includes a third surface and a fourth surface intersecting the third surface. The fourth surface includes a second surface region. The second surface region is continuous with the third surface. The direction from the first surface region to the second surface region is along a first direction. The first surface region and the second surface region are along a second direction and a third direction. The third direction intersects with a plane including the first direction and the second direction. The first surface and the third surface are along the third direction. The laminate is provided between the first surface region and the second surface region. The laminate includes a first magnetic layer and a second magnetic layer provided between the first magnetic layer and the second surface region. The second magnetic layer includes a second magnetic layer surface facing the second surface region, and a width ratio of a second width of the second magnetic layer surface along the third direction to a first width of the first surface region along the third direction is 0.25 or more and 0.92 or less. [Brief explanation of the drawings]

[0006] [Figure 1] 1A and 1B are schematic views illustrating the magnetic head according to the first embodiment. [Figure 2] FIG. 2 is a schematic cross-sectional view illustrating the magnetic recording device according to the first embodiment. [Figure 3] FIG. 3 is a graph illustrating the characteristics of the magnetic head. [Figure 4] FIG. 4 is a graph illustrating the characteristics of the magnetic head. [Figure 5] FIG. 5 is a schematic view illustrating the operation of the magnetic head according to the first embodiment. [Figure 6] FIG. 6 is a schematic plan view illustrating the magnetic head according to the first embodiment. [Figure 7] FIG. 7 is a schematic plan view illustrating the magnetic head according to the first embodiment. [Figure 8] FIG. 8 is a schematic plan view illustrating the magnetic head according to the first embodiment. [Figure 9] 9A and 9B are schematic views illustrating the magnetic head according to the first embodiment. [Figure 10] 10A and 10B are schematic views illustrating the magnetic head according to the first embodiment. [Figure 11] FIG. 11 is a schematic perspective view illustrating the magnetic recording device according to the embodiment. [Figure 12] FIG. 12 is a schematic perspective view illustrating a part of the magnetic recording device according to the embodiment. [Figure 13] FIG. 13 is a schematic perspective view illustrating the magnetic recording device according to the embodiment. [Figure 14] 14A and 14B are schematic perspective views illustrating a part of the magnetic recording device according to the embodiment. DETAILED DESCRIPTION OF THE INVENTION

[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 may be different depending on the drawing. In this specification and in each drawing, elements similar to those previously described with reference to the previous drawings are designated by the same reference numerals, and detailed descriptions thereof will be omitted where 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 also 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 will be described later, 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.

[0011] The direction from the magnetic recording medium 80 to the magnetic head 110 is defined as the Z-axis direction. A 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, for example, the height direction. The X-axis direction corresponds to, for example, the down-track direction. The Y-axis direction corresponds to, for example, the cross-track direction. 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 at the desired position on the magnetic recording medium 80 is controlled to a direction corresponding to the recording magnetic field. This allows information to be recorded on the magnetic recording medium 80. For example, perpendicular magnetic recording is performed.

[0012] As shown in FIG. 2, a coil 30c is provided. In this example, a portion of the coil 30c is located 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 located between the shield 33 and the second magnetic pole 32. Another portion of the coil 30c is located 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 also include side shields (not shown).

[0013] 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.

[0014] 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 extends along, for example, the XY plane.

[0015] 2, an 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 a first wiring W1 and the first magnetic pole 31. The second terminal T2 is electrically connected to the laminate 20 via a second wiring W2 and the second magnetic pole 32. For example, a current (e.g., a direct current) is supplied to the laminate 20 from the electric circuit 20D.

[0016] As shown in FIG. 1(b), a current i is supplied to the laminate 20. The current i is supplied, for example, from the electric circuit 20D described above. As shown in FIG. 1(b), in this example, the current i is directed from the second magnetic layer 22 to the first magnetic layer 21. As shown in FIG. 1(b), the electron flow je accompanying the current i is directed from the first magnetic layer 21 to the second magnetic layer 22. The direction of the current i is from the second magnetic pole 32 to the first magnetic pole 31.

[0017] For example, when a current i equal to or greater than a threshold value 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 oscillation occurs, an alternating magnetic field (for example, a high-frequency magnetic field) is generated from the stack 20. The alternating magnetic field generated in the stack 20 is applied to the magnetic recording medium 80, thereby assisting writing to the magnetic recording medium 80. For example, microwave-assisted magnetic recording (MAMR) can be implemented.

[0018] 1(a) and 1(b), in this example, the stack 20 includes a third magnetic layer 23, a fourth magnetic layer 24, a first non-magnetic layer 41, a second non-magnetic layer 42, a third non-magnetic layer 43, a fourth non-magnetic layer 44, and a fifth non-magnetic layer 45. The insulating portion 30i is omitted from FIGS. 1(a) and 1(b).

[0019] The first magnetic pole 31 includes a first surface F1 and a second surface F2. The second surface F2 intersects with the first surface F1. The second surface F2 includes a first surface region r1. The first surface region r1 is continuous with the first surface F1. The first surface F1 corresponds to the medium facing surface 30F.

[0020] The second magnetic pole 32 includes a third surface F3 and a fourth surface F4. The fourth surface F4 intersects with the third surface F3. The fourth surface F4 includes a second surface region r2. The second surface region r2 is continuous with the third surface F3. The third surface F3 is, for example, along a plane that includes the first surface F1.

[0021] The direction from the first surface region r1 to the second surface region r2 is along the first direction D1. The first surface region r1 and the second surface region r2 are along the second direction D2 and the third direction D3. The third direction D3 intersects with a plane including the first direction D1 and the second direction D2. The first surface F1 and the third surface F3 are along the third direction D3. The laminate 20 is provided between the first surface region r1 and the second surface region r2.

[0022] The third direction D3 is, for example, along the Y-axis direction. The first direction D1 may be along the X-axis direction. The first direction D1 is along the gap direction (the direction of the gap between the first magnetic pole 31 and the second magnetic pole 32). The first direction D1 may be inclined with respect to the X-axis direction. The first direction D1 corresponds to the stacking direction of the laminate 20. The second direction D2 may correspond to the height direction. The second direction D2 may be inclined with respect to the Z-axis direction.

[0023] The stack 20 includes a first magnetic layer 21 and a second magnetic layer 22. The second magnetic layer 22 is provided between the first magnetic layer 21 and the second surface region r2.

[0024] 1(a) and 1(b), the second magnetic layer 22 includes a second magnetic layer surface 22F. The second magnetic layer surface 22F faces the second surface region r2. The second magnetic layer surface 22F is the surface on the side of the second surface region r2.

[0025] As shown in FIG. 1B, the width of the first surface region r1 along the third direction D3 is defined as a first width w1. The width of the second magnetic layer surface 22F along the third direction D3 is defined as a second width w2. In the embodiment, the width ratio (w2 / w1) of the second width w2 to the first width w1 is 0.25 or more and 0.92 or less. This allows an alternating magnetic field to be generated efficiently, as will be described later. Efficient MAMR can be implemented. According to the embodiment, a magnetic head capable of improving recording density can be provided.

[0026] As shown in FIG. 1(a), the second surface F2 may further include a third surface region r3. The first surface region r1 is located between the first surface F1 and the third surface region r3. The third surface region r3 is aligned along the second direction D2 and the third direction D3. The third surface region r3 is substantially parallel to the first surface region r1. The third surface region r3 is continuous with the first surface region r1.

[0027] As shown in Figure 1(a), the fourth surface F4 further includes a fourth surface region r4 and a fifth surface region r5. The direction from the third surface region r3 to the fourth surface region r4 is along the first direction D1. The fourth surface region r4 is along the second direction D2 and the third direction D3. The fourth surface region r4 is substantially parallel to the second surface region r2.

[0028] The distance along the first direction D1 between the first surface region r1 and the second surface region r2 is defined as a first distance d1. The distance along the first direction D1 between the third surface region r3 and the fourth surface region r4 is defined as a second distance d2. The first distance d1 is shorter than the second distance d2.

[0029] The fifth surface region r5 is located between the second surface region r2 and the fourth surface region r4. A plane including the fifth surface region r5 intersects with a plane including the third surface region r3 and a plane including the fourth surface region r4.

[0030] The second magnetic pole 32 includes an intersection position 32p between a plane including the fifth surface region r5 and a plane including the fourth surface region r4. In one example, the intersection position 32p is on the fourth surface F4. In one example, the intersection position 32p is located inside the second magnetic pole 32. The length along the second direction D2 between the intersection position 32p and the third surface F3 is defined as a first length L1. The first length L1 corresponds to, for example, the effective height of the second magnetic pole 32.

[0031] The length of the second magnetic layer surface 22F along the second direction D2 is defined as the second length L2. The second length L2 corresponds to, for example, the effective height of the second magnetic layer surface 22F. The ratio of the second length L2 to the first length L1 (L2 / L1) is defined as the length ratio. In the embodiment, it is preferable that the ratio is, for example, 0.1 or more and 0.85 or less. This allows an alternating magnetic field to be generated efficiently, as will be described later. Efficient MAMR can be implemented. According to the embodiment, a magnetic head capable of improving recording density can be provided.

[0032] 1(a) and 1(b), in the magnetic head 110, the stack 20 may include, for example, a third magnetic layer 23, a fourth magnetic layer 24, a first non-magnetic layer 41, a second non-magnetic layer 42, a third non-magnetic layer 43, a fourth non-magnetic layer 44, and a fifth non-magnetic layer 45. The third magnetic layer 23 is provided between the first magnetic pole 31 and the first magnetic layer 21. The fourth magnetic layer 24 is provided between the first magnetic layer 21 and the second magnetic layer 22.

[0033] The first non-magnetic layer 41 is provided between the first magnetic pole 31 and the third magnetic layer 23. The second non-magnetic layer 42 is provided between the third magnetic layer 23 and the first magnetic layer 21. The third non-magnetic layer is provided between the first magnetic layer 21 and the fourth magnetic layer 24. The fourth non-magnetic layer 44 is provided between the fourth magnetic layer 24 and the second magnetic layer 22. The fifth non-magnetic layer 45 is provided between the second magnetic layer 22 and the second magnetic pole 32.

[0034] 1(b), the thickness of the first magnetic layer 21 along the first direction D1 is defined as a first thickness t1. The thickness of the second magnetic layer 22 along the first direction D1 is defined as a second thickness t2. The thickness of the third magnetic layer 23 along the first direction D1 is defined as a third thickness t3. The thickness of the fourth magnetic layer 24 along the first direction D1 is defined as a fourth thickness t4.

[0035] In the magnetic head 110, the first thickness t1 is thicker than the third thickness t3. The second thickness t2 is thicker than the fourth thickness t4. The third thickness t3 is, for example, 0.7 times or less the first thickness t1. The fourth thickness t4 is, for example, 0.75 times or less the second thickness t2. For example, the third thickness t3 may be 0.1 times or more the first thickness t1. For example, the fourth thickness t4 may be 0.1 times or more the second thickness t2.

[0036] For example, the first magnetic layer 21 and the second magnetic layer 22 may function as an oscillation layer. The third magnetic layer 23 and the fourth magnetic layer 24 may function as a spin injection layer. At least one of the first magnetic layer 21, the second magnetic layer 22, the third magnetic layer 23, and the fourth magnetic layer 24 may include at least one selected from the group consisting of Fe, Co, and Ni.

[0037] In one example of the magnetic head 110, the first thickness t1 is, for example, 3 nm or more and 15 nm or less. The first thickness t1 may be, for example, 5 nm or more and 15 nm or less. The second thickness t2 is, for example, 5 nm or more and 15 nm or less. The third thickness t3 is, for example, 0.5 nm or more and 5 nm or less. The fourth thickness t4 is, for example, 0.5 nm or more and 8 nm or less.

[0038] In the magnetic head 110, the first non-magnetic layer 41 includes, for example, at least one selected from the group consisting of Ru, Ir, Ta, Rh, Pd, Pt, and W. The second non-magnetic layer 42 includes, for example, at least one selected from the group consisting of Cu, Au, Cr, Al, V, and Ag. For example, the third non-magnetic layer 43 includes, for example, at least one selected from the group consisting of Cu, Au, Cr, Al, V, and Ag, and the fourth non-magnetic layer 44 includes, for example, at least one selected from the group consisting of Ru, Ir, Ta, Rh, Pd, Pt, and W. Alternatively, for example, the third non-magnetic layer 43 includes, for example, at least one selected from the group consisting of Ru, Ir, Ta, Rh, Pd, Pt, and W, and the fourth non-magnetic layer 44 includes, for example, at least one selected from the group consisting of Cu, Au, Cr, Al, V, and Ag. The fifth nonmagnetic layer 45 includes, for example, at least one selected from the group consisting of Cu, Au, Cr, Al, V, and Ag.

[0039] As shown in FIG. 1(b), the thickness of the first non-magnetic layer 41 along the first direction D1 is referred to as a first non-magnetic layer thickness t41. The thickness of the second non-magnetic layer 42 along the first direction D1 is referred to as a second non-magnetic layer thickness t42. The thickness of the third non-magnetic layer 43 along the first direction D1 is referred to as a third non-magnetic layer thickness t43. The thickness of the fourth non-magnetic layer 44 along the first direction D1 is referred to as a fourth non-magnetic layer thickness t44. The thickness of the fifth non-magnetic layer 45 along the first direction D1 is referred to as a fifth non-magnetic layer thickness t45.

[0040] In one example of the magnetic head 110, the first non-magnetic layer thickness t41 is, for example, 2 nm or more and 8 nm or less. The second non-magnetic layer thickness t42 is, for example, 1 nm or more and 5 nm or less. The third non-magnetic layer thickness t43 is, for example, 1 nm or more and 8 nm or less. The fourth non-magnetic layer thickness t44 is, for example, 1 nm or more and 8 nm or less. The fifth non-magnetic layer thickness t45 is, for example, 1 nm or more and 8 nm or less.

[0041] As shown in FIG. 1( a), the first magnetic layer 21 has a surface on the side of the second magnetic layer 22. The length of that surface of the first magnetic layer 21 along the second direction D2 is defined as a third length L3. In the embodiment, the third length L3 is longer than the second length L2. As shown in FIG. 1( b), the first magnetic layer 21 has a surface on the side of the second magnetic layer 22. The width of that surface of the first magnetic layer 21 along the third direction D3 is defined as a third width w3. In the embodiment, the third width w3 is wider than the second width w2. For example, the size of the first magnetic layer 21 is larger than the size of the second magnetic layer 22. For example, the resistance of the first magnetic layer 21 is lower than the resistance of the second magnetic layer 22.

[0042] An example of the results of a simulation of the characteristics of the magnetic head 110 will now be described. FIG. 3 is a graph illustrating the characteristics of the magnetic head. The horizontal axis of FIG. 3 is the width ratio Rw1. As already explained, the width ratio Rw1 is the ratio (w2 / w1) of the second width w2 to the first width w1. The first width w1 is the width of the first surface region r1 along the third direction D3. The second width w2 is the width of the second magnetic layer surface 22F along the third direction D3. The vertical axis of FIG. 3 is a parameter P1 related to the magnitude of the alternating change in resistance in the second magnetic layer 22. The parameter P1 is normalized. When the parameter P1 is large, the alternating change in resistance in the second magnetic layer 22 is large. When the alternating change in resistance is large, alternating power associated with the alternating change in resistance acts on the first magnetic layer 21. This allows an alternating magnetic field to be efficiently generated from the first magnetic layer 21.

[0043] The simulation conditions are as follows: The first width w1 is 60 nm. The second width w2 varies. The first length L1 is 50 nm. The second length L2 is 35 nm. The first thickness t1 is 5 nm. The second thickness t2 is 5 nm. The third thickness t3 is 2 nm. The fourth thickness t4 is 2 nm. The first non-magnetic layer thickness t41 is 4 nm. The second non-magnetic layer thickness t42 is 2 nm. The third non-magnetic layer thickness t43 is 2 nm. The fourth non-magnetic layer thickness t44 is 3 nm. The fifth non-magnetic layer thickness t45 is 2 nm.

[0044] As shown in Figure 3, when the width ratio Rw1 is 0.25 or more and 0.92 or less, a parameter P1 of 0.5 or more is obtained. In the embodiment, the width ratio Rw1 is preferably 0.25 or more and 0.92 or less. When the width ratio Rw1 is 0.25 or more and 0.92 or less, the alternating power accompanying the resistance change increases. The action of the alternating power effectively generates an alternating magnetic field.

[0045] The width ratio Rw1 may be 0.4 or more and 0.85 or less. A parameter P1 of 0.75 or more can be obtained. An alternating magnetic field is generated more effectively.

[0046] The reason why a large parameter P1 is obtained when the width ratio Rw1 is 0.25 or more and 0.92 or less is thought to be, for example, due to an increase in the component parallel to the second magnetic layer surface 22F of the magnetic field applied to the second magnetic layer 22 from the first magnetic pole 31 and the second magnetic pole 32. It is thought that the alternating change in resistance at the interface of the second magnetic layer 22 becomes large. The interface is, for example, the second magnetic layer surface 22F.

[0047] FIG. 4 is a graph illustrating the characteristics of the magnetic head. The horizontal axis of FIG. 4 is the length ratio RL1. As already explained, the length ratio RL1 is the ratio (L2 / L1) of the second length L2 to the first length L1. The second length L2 is the length (height) of the second magnetic layer surface 22F along the second direction D2. The first length L1 is the length (height) between the intersection position 32p and the third surface F3 along the second direction D2. The vertical axis of FIG. 4 is the parameter P1.

[0048] In the example of FIG. 4, the first width w1 is 60 nm. The second width w2 is 40 nm. The first length L1 is 50 nm. The second length L2 varies. The first thickness t1 is 5 nm. The second thickness t2 is 5 nm. The third thickness t3 is 2 nm. The fourth thickness t4 is 2 nm. The first non-magnetic layer thickness t41 is 4 nm. The second non-magnetic layer thickness t42 is 2 nm. The third non-magnetic layer thickness t43 is 2 nm. The fourth non-magnetic layer thickness t44 is 3 nm. The fifth non-magnetic layer thickness t45 is 2 nm.

[0049] As shown in FIG. 4, when the length ratio RL1 is 0.1 or more and 0.85 or less, a parameter P1 of 0.5 or more is obtained. This increases the alternating power associated with the resistance change. The alternating power acts to effectively generate an alternating magnetic field. In the embodiment, the length ratio RL1 is preferably 0.1 or more and 0.85 or less. When the length ratio RL1 is 0.1 or more and 0.85 or less, the alternating power associated with the resistance change increases. The alternating magnetic field is effectively generated by the alternating power.

[0050] The length ratio RL1 may be greater than or equal to 0.2 and less than or equal to 0.72. This results in a parameter P1 of 0.75 or greater. This allows for a more effective generation of an alternating magnetic field.

[0051] When the length ratio RL1 is 0.1 or more and 0.85 or less, a large parameter P1 is obtained. This is thought to be due to, for example, an increase in the component parallel to the second magnetic layer surface 22F of the magnetic field applied to the second magnetic layer 22 from the first magnetic pole 31 and the second magnetic pole 32. For example, it is thought that the alternating change in resistance at the interface of the resistance of the second magnetic layer 22 becomes large. The interface is, for example, the second magnetic layer surface 22F. When the length ratio RL1 is 0.2 or more and 0.7 or less, an even larger parameter P1 is obtained. This is thought to be due to a further increase in the component parallel to the second magnetic layer surface 22F of the magnetic field applied to the second magnetic layer 22 from the first magnetic pole 31 and the second magnetic pole 32.

[0052] FIG. 5 is a schematic view illustrating the operation of the magnetic head according to the first embodiment. As shown in FIG. 5, when a current i c equal to or greater than a threshold flows through the laminate 20, the resistance between the first terminal T1 and the second terminal T2 changes alternately. The alternating change in resistance generates an alternating power Pa1. The alternating power Pa1 is added to (superimposed on) the current i c. For example, the magnetization 22M of the second magnetic layer 22 oscillates, causing the resistance of the second magnetic layer 22 to change alternately. When a current i c equal to or greater than the threshold flows through the first magnetic layer 21, the magnetization 21M of the first magnetic layer 21 oscillates. An alternating magnetic field Ha1 is generated from the first magnetic layer 21. The alternating power Pa1 based on the change in resistance of the second magnetic layer 22 acts on the first magnetic layer 21. The frequency of the alternating magnetic field Ha1 and the frequency of the alternating power Pa1 can be substantially the same. For example, the alternating magnetic field Ha1 and the alternating power Pa1 are synchronized. For example, a current magnetic field may be generated by the alternating power Pa1, and the generated current magnetic field may be superimposed on the alternating magnetic field Ha1.

[0053] The alternating power Pa1 from the second magnetic layer 22 acts effectively on the first magnetic layer 21, thereby generating an alternating magnetic field Ha1 with high efficiency. For example, the action of the alternating power Pa1 stabilizes the oscillation of the magnetization 21M of the first magnetic layer 21, and the alternating magnetic field Ha1 is generated with high efficiency. An efficient resistance change is obtained in the second magnetic layer 22, allowing high-intensity alternating power Pa1 to act on the first magnetic layer 21.

[0054] In the embodiment, an efficient resistance change can be obtained by setting the width ratio Rw1 in an appropriate range, and an efficient resistance change can be obtained by setting the length ratio RL1 in an appropriate range.

[0055] In this way, in the magnetic head 110, for example, when a current ic flows through the laminate 20, an alternating magnetic field Ha1 is generated from the laminate 20, and an alternating power Pa1 is generated in the laminate 20. For example, the absolute value of the difference between the first frequency of the alternating magnetic field Ha1 and the second frequency of the alternating power Pa1 is 0.25 times or less of the first frequency. The absolute value of the difference may also be 0.1 times or less of the first frequency.

[0056] In one example, at least a portion of the alternating power Pa1 is generated in the second magnetic layer 22. In one example, at least a portion of the alternating magnetic field Ha1 is generated from the first magnetic layer 21. For example, it is considered that at least a portion of the alternating power Pa1 is generated from a magnetic layer having a small size. For example, it is considered that at least a portion of the alternating magnetic field Ha1 is generated from a magnetic layer having a large size.

[0057] A magnetic recording device 210 according to the embodiment includes a magnetic head 110 and an electric circuit 20D. The magnetic head 110 includes a first magnetic pole 31, a second magnetic pole 32, and a stack 20. The stack 20 is provided between the first magnetic pole 31 and the second magnetic pole 32. The electric circuit 20D is capable of supplying a current to the stack 20. The stack 20 includes a first magnetic layer 21 and a second magnetic layer 22 provided between the first magnetic layer 21 and the second magnetic pole 32. When a current i c flows through the stack 20, an alternating magnetic field Ha1 is generated from the stack 20, and an alternating power Pa1 is generated in the stack 20.

[0058] In the magnetic recording device 210, the absolute value of the difference between the first frequency of the alternating magnetic field Ha1 and the second frequency of the alternating power Pa1 is 0.25 times or less of the first frequency. The absolute value of the difference may be 0.1 times or less of the first frequency. The first frequency is, for example, 15 GHz or more and 50 GHz or less. The alternating magnetic field Ha1 of the first frequency is applied to the magnetic recording medium 80, and MAMR is effectively performed.

[0059] 6 to 8 are schematic plan views illustrating the magnetic head according to the first embodiment. These figures are plan views seen from the arrow AR1 in FIG. 1(a). 6, in the magnetic head 110a according to the embodiment, the width of the first magnetic pole 31 (for example, the first width w1 of the first surface region r1) may be wider than the width of the laminate 20. The width of the laminate 20 is, for example, the maximum length of the laminate 20 in the third direction D3.

[0060] 7, in the magnetic head 110b according to the embodiment, the width of the first magnetic pole 31 (for example, the first width w1 of the first surface region r1) may be narrower than the width of the laminate 20. The width of the laminate 20 is, for example, the maximum length of the laminate 20 in the third direction D3.

[0061] 8, in the magnetic head 110c according to the embodiment, the position of the first magnetic pole 31 in the third direction D3 may be shifted from the position of the laminate 20 in the third direction D3. The position of the first magnetic pole 31 in the third direction D3 may be, for example, the center position of the first magnetic pole 31 in the third direction D3. The position of the laminate 20 in the third direction D3 may be, for example, the center position of the laminate 20 in the third direction D3.

[0062] Except for the above, the configuration of the magnetic heads 110a, 110b, and 110c may be the same as that of the magnetic head 110. A magnetic head capable of improving recording density can be provided.

[0063] 9A and 9B are schematic views illustrating the magnetic head according to the first embodiment. Fig. 9(a) is a cross-sectional view, and Fig. 9(b) is a plan view seen from the arrow AR1 in Fig. 9(a). 9(a) and 9(b), the magnetic head 111 according to the embodiment also includes a first magnetic pole 31, a second magnetic pole 32, and a laminate 20. The configuration of the laminate 20 in the magnetic head 111 is different from the configuration of the laminate 20 in the magnetic head 110. Except for this, the configuration of the magnetic head 111 may be the same as the configuration of the magnetic head 110.

[0064] In the magnetic head 111, the stack 20 includes a first magnetic layer 21, a second magnetic layer 22, a third magnetic layer 23, a fourth magnetic layer 24, a first non-magnetic layer 41, a second non-magnetic layer 42, a third non-magnetic layer 43, a fourth non-magnetic layer 44, and a fifth non-magnetic layer 45. The second magnetic layer 22 is provided between the first magnetic layer 21 and the second magnetic pole 32. The third magnetic layer 23 is provided between the first magnetic layer 21 and the second magnetic layer 22. The fourth magnetic layer 24 is provided between the second magnetic layer 22 and the second magnetic pole 32. The first non-magnetic layer 41 is provided between the first magnetic pole 31 and the first magnetic layer 21. The second non-magnetic layer 42 is provided between the first magnetic layer 21 and the third magnetic layer 23. The third non-magnetic layer 43 is provided between the third magnetic layer 23 and the second magnetic layer 22. The fourth non-magnetic layer 44 is provided between the second magnetic layer 22 and the fourth magnetic layer 24. The fifth non-magnetic layer 45 is provided between the fourth magnetic layer 24 and the second magnetic pole 32.

[0065] The first thickness t1 of the first magnetic layer 21 along the first direction D1 is thicker than the third thickness t3 of the third magnetic layer 23 along the first direction D1. The second thickness t2 of the second magnetic layer 22 along the first direction D1 is thicker than the fourth thickness t4 of the fourth magnetic layer 24 along the first direction D1. The third thickness t3 is, for example, 0.75 times or less the first thickness t1. The fourth thickness t4 is, for example, 0.7 times or less the second thickness t2.

[0066] The magnetic head 111 also achieves the same characteristics as the magnetic head 110. For example, when the width ratio Rw1 is 0.25 or more and 0.92 or less, a high parameter P1 is obtained. In the magnetic head 111, the width ratio Rw1 is preferably 0.25 or more and 0.92 or less. The width ratio Rw1 may be 0.4 or more and 0.85 or less. A highly efficient resistance change is obtained, and an alternating magnetic field is generated more effectively.

[0067] In the magnetic head 111, a high parameter P1 is obtained when the length ratio RL1 is 0.1 or more and 0.85 or less. In the magnetic head 111, the length ratio RL1 is preferably 0.1 or more and 0.85 or less. The length ratio RL1 may be 0.2 or more and 0.72 or less. A highly efficient resistance change is obtained, and an alternating magnetic field is generated more effectively.

[0068] Efficient MAMR can also be implemented in the magnetic head 111. According to the embodiment, it is possible to provide a magnetic head that can improve recording density.

[0069] In the magnetic head 111, the first non-magnetic layer 41 includes at least one selected from the group consisting of Cu, Au, Cr, Al, V, and Ag. For example, the second non-magnetic layer 42 includes at least one selected from the group consisting of Ru, Ir, Ta, Rh, Pd, Pt, and W, and the third non-magnetic layer 43 includes at least one selected from the group consisting of Cu, Au, Cr, Al, V, and Ag. Alternatively, the second non-magnetic layer 42 includes at least one selected from the group consisting of Cu, Au, Cr, Al, V, and Ag, and the third non-magnetic layer 43 includes at least one selected from the group consisting of Ru, Ir, Ta, Rh, Pd, Pt, and W. The fourth non-magnetic layer 44 includes at least one selected from the group consisting of Cu, Au, Cr, Al, V, and Ag. The fifth nonmagnetic layer 45 includes at least one selected from the group consisting of Ru, Ir, Ta, Rh, Pd, Pt, and W, for example.

[0070] In one example of the magnetic head 111, the first non-magnetic layer thickness t41 is, for example, 1 nm or more and 8 nm or less. The second non-magnetic layer thickness t42 is, for example, 1 nm or more and 8 nm or less. The third non-magnetic layer thickness t43 is, for example, 1 nm or more and 8 nm or less. The fourth non-magnetic layer thickness t44 is, for example, 1 nm or more and 5 nm or less. The fifth non-magnetic layer thickness t45 is, for example, 2 nm or more and 8 nm or less.

[0071] 9(b), in the magnetic head 111, a current i is supplied to the stack 20. For example, the current i is directed from the first magnetic layer 21 to the second magnetic layer 22. The electron current j is directed from the second magnetic layer 22 to the first magnetic layer 21.

[0072] 10A and 10B are schematic views illustrating the magnetic head according to the first embodiment. Fig. 10(a) is a cross-sectional view, and Fig. 10(b) is a plan view seen from the arrow AR1 in Fig. 10(a). 10(a) and 10(b), the magnetic head 112 according to the embodiment also includes a first magnetic pole 31, a second magnetic pole 32, and a laminate 20. The configuration of the laminate 20 in the magnetic head 112 is different from the configuration of the laminate 20 in the magnetic head 110. Except for this, the configuration of the magnetic head 112 may be the same as the configuration of the magnetic head 110.

[0073] In the magnetic head 112, the stack 20 includes a first non-magnetic layer 41. The first non-magnetic layer 41 is provided between the first magnetic pole 31 and the first magnetic layer 21. The first non-magnetic layer 41 includes at least one selected from the group consisting of Ru, Ir, Ta, Rh, Pd, Pt, and W, for example.

[0074] In the magnetic head 112, the stack 20 may include a second non-magnetic layer 42. The second non-magnetic layer 42 is provided between the first magnetic layer 21 and the second magnetic layer 22. In one example, the second non-magnetic layer 42 includes at least one selected from the group consisting of, for example, Ru, Ir, Ta, Rh, Pd, Pt, and W. In another example, the second non-magnetic layer 42 may include at least one selected from the group consisting of, for example, Cu, Au, Cr, Al, V, and Ag.

[0075] In the magnetic head 112, the stack 20 may include a third non-magnetic layer 43. The third non-magnetic layer 43 is provided between the second magnetic layer 22 and the second magnetic pole 32. In one example, the third non-magnetic layer 43 includes at least one selected from the group consisting of Cu, Au, Cr, Al, V, and Ag. In another example, the third non-magnetic layer 43 may include at least one selected from the group consisting of Ru, Ir, Ta, Rh, Pd, Pt, and W.

[0076] The magnetic head 112 also achieves characteristics similar to those of the magnetic head 110. For example, a high parameter P1 is obtained when the width ratio Rw1 is 0.25 or more and 0.92 or less. The width ratio Rw1 is also preferably 0.25 or more and 0.92 or less in the magnetic head 111. The width ratio Rw1 may be 0.4 or more and 0.85 or less. A highly efficient resistance change is obtained, and an alternating magnetic field is generated more effectively.

[0077] In the magnetic head 112, a high parameter P1 is obtained when the length ratio RL1 is 0.1 or more and 0.85 or less. In the magnetic head 111, the length ratio RL1 is preferably 0.1 or more and 0.85 or less. The length ratio RL1 may be 0.2 or more and 0.72 or less. A highly efficient resistance change is obtained, and an alternating magnetic field is generated more effectively.

[0078] Efficient MAMR can also be implemented in the magnetic head 112. According to the embodiment, a magnetic head capable of improving recording density can be provided.

[0079] In one example of the magnetic head 112, the first non-magnetic layer thickness t41 is, for example, 2 nm or more and 8 nm or less, the second non-magnetic layer thickness t42 is, for example, 1 nm or more and 8 nm or less, and the third non-magnetic layer thickness t43 is, for example, 1 nm or more and 8 nm or less.

[0080] 10(b), in one example of the magnetic head 112, the current i c is oriented from the second magnetic layer 22 to the first magnetic layer 21. The electron current je is oriented from the first magnetic layer 21 to the second magnetic layer 22. In another example of the magnetic head 112, the current i c may be oriented from the first magnetic layer 21 to the second magnetic layer 22.

[0081] In the magnetic head 112, for example, the first magnetic layer 21 is capable of oscillation, and the second magnetic layer 22 is capable of oscillation.

[0082] In the magnetic heads 111 and 112, for example, when a current ic flows through the laminate 20, an alternating magnetic field Ha1 is generated from the laminate 20, and alternating power Pa1 is generated in the laminate 20. For example, the absolute value of the difference between the first frequency of the alternating magnetic field Ha1 and the second frequency of the alternating power Pa1 is 0.25 times or less of the first frequency.

[0083] The configuration described for magnetic head 110 may be applied to magnetic head 111 and magnetic head 112. For example, the third length L3 (see FIG. 1(a)) is longer than the second length L2. For example, the third width w3 (see FIG. 1(b)) is wider than the second width w2.

[0084] The magnetic heads 111 and 112 may have the same configurations as those described for the magnetic heads 110a, 110b, and 110c.

[0085] An example of the magnetic head and magnetic recording medium 80 included in the magnetic recording device 210 according to the embodiment will be described below.

[0086] FIG. 11 is a schematic perspective view illustrating the magnetic recording device according to the embodiment. 11, 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.

[0087] The magnetic recording medium 80 includes, for example, a medium substrate 82 and a magnetic recording layer 81 provided on the medium substrate 82. The magnetization 83 of the magnetic recording layer 81 is controlled by the recording unit 60.

[0088] 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.

[0089] 11 , magnetic recording medium 80 moves relative to magnetic head 110 in medium movement direction 85. Information corresponding to magnetization 83 of magnetic recording layer 81 is controlled by magnetic head 110 at any position. Information corresponding to magnetization 83 of magnetic recording layer 81 is reproduced by magnetic head 110 at any position.

[0090] FIG. 12 is a schematic perspective view illustrating a part of the magnetic recording device according to the embodiment. FIG. 12 illustrates a head slider. The magnetic head 110 is provided on a head slider 159. The head slider 159 includes, for example, Al2O3 / TiC. The head slider 159 moves relative to the magnetic recording medium while floating above or in contact with the magnetic recording medium.

[0091] The head slider 159 has, for example, an air inflow side 159A and an air outflow side 159B. The magnetic head 110 is disposed on the side 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.

[0092] FIG. 13 is a schematic perspective view illustrating the magnetic recording device according to the embodiment. As shown in FIG. 13, a rotary actuator is used in a magnetic recording device 150 according to the embodiment. A recording medium disk 180 is mounted on a spindle motor 180M. The recording medium disk 180 is rotated in the direction of 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 also include a recording medium 181. The recording medium 181 is, for example, an SSD (Solid State Drive). The recording medium 181 may be, for example, a non-volatile memory such as a flash memory. For example, the magnetic recording device 150 may be a hybrid HDD (Hard Disk Drive).

[0093] 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.

[0094] When the recording medium disk 180 rotates, the pressing pressure from the suspension 154 and the pressure generated at the air bearing surface (ABS) of the head slider 159 are balanced. The distance between the air bearing 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 traveling type may be applied.

[0095] 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.

[0096] Arm 155 is held by ball bearings. The ball bearings are provided at two locations, above and below bearing portion 157. Arm 155 can rotate and slide using voice coil motor 156. The magnetic head can be moved to any position on recording medium disk 180.

[0097] 14A and 14B are schematic perspective views illustrating a part of the magnetic recording device according to the embodiment. 14(a) illustrates a partial configuration of the magnetic recording device, and is an enlarged perspective view of a head stack assembly 160. FIG. 14(b) is a perspective view illustrating a magnetic head assembly (head gimbal assembly: HGA) 158 that is part of the head stack assembly 160.

[0098] 14(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 in the opposite direction to the head gimbal assembly 158. The support frame 161 supports a coil 162 of the voice coil motor 156.

[0099] As shown in FIG. 14( 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 .

[0100] A head slider 159 is provided at the tip of the suspension 154. The head slider 159 is provided with the magnetic head according to the embodiment.

[0101] 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.

[0102] The suspension 154 has, for example, lead wires (not shown) for recording and reproducing signals. The suspension 154 may also have, for example, lead wires (not shown) for a heater for adjusting the flying height. The suspension 154 may also have lead wires (not shown) for, for example, a spin transfer torque oscillator. These lead wires are electrically connected to a plurality of electrodes provided on the magnetic head.

[0103] The magnetic recording device 150 is provided with a signal processing unit 190. 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.

[0104] 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 enables the magnetic recording medium and the magnetic head to be moved relatively 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.

[0105] For example, the magnetic recording medium is a recording medium disk 180. The movable part includes, for example, a head slider 159. The position control unit includes, for example, a head gimbal assembly 158.

[0106] The embodiment may include the following configurations (for example, technical solutions). (Configuration 1) a first magnetic pole including a first surface and a second surface intersecting the first surface, the second surface including a first surface region continuous with the first surface; a second magnetic pole, the second magnetic pole including a third surface and a fourth surface intersecting the third surface, the fourth surface including a second surface region, the second surface region being continuous with the third surface, a direction from the first surface region to the second surface region being along a first direction, the first surface region and the second surface region being along a second direction and a third direction, the third direction intersecting a plane including the first direction and the second direction, and the first surface and the third surface being along the third direction; a laminate provided between the first surface region and the second surface region; Equipped with The laminate is a first magnetic layer; a second magnetic layer provided between the first magnetic layer and the second surface region; Including, the second magnetic layer includes a second magnetic layer surface facing the second surface region, a width ratio of a second width of the second magnetic layer surface along the third direction to a first width of the first surface region along the third direction is not less than 0.25 and not more than 0.92.

[0107] (Configuration 2) 2. The magnetic head according to configuration 1, wherein the width ratio is 0.4 or more and 0.85 or less.

[0108] (Configuration 3) the second surface further includes a third surface region; the first surface region is between the first surface and the third surface region; The third surface region is aligned along the second direction and the third direction, the fourth surface further includes a fourth surface region and a fifth surface region; a direction from the third surface region to the fourth surface region is along the first direction; The fourth surface region is aligned along the second direction and the third direction, a first distance along the first direction between the first surface region and the second surface region is shorter than a second distance along the first direction between the third surface region and the fourth surface region; the fifth surface region is between the second surface region and the fourth surface region; a plane including the fifth surface region intersects with a plane including the third surface region and a plane including the fourth surface region, the second magnetic pole has a first length along the second direction between the third surface and an intersection position of a plane including the fifth surface region and a plane including the fourth surface region, 3. The magnetic head according to configuration 1 or 2, wherein a ratio of a second length of the second magnetic layer surface along the second direction to the first length is 0.1 or more and 0.85 or less.

[0109] (Configuration 4) 4. The magnetic head according to configuration 3, wherein the length ratio is equal to or greater than 0.2 and equal to or less than 0.72.

[0110] (Configuration 5) 5. The magnetic head according to any one of configurations 1 to 4, wherein the second direction is inclined with respect to the first direction.

[0111] (Configuration 6) a first magnetic pole including a first surface and a second surface intersecting the first surface, the second surface including a first surface region continuous with the first surface; a second magnetic pole, the second magnetic pole including a third surface and a fourth surface intersecting the third surface, the fourth surface including a second surface region, the second surface region being continuous with the third surface, a direction from the first surface region to the second surface region being along a first direction, the first surface region and the second surface region being along a second direction and a third direction, the third direction intersecting a plane including the first direction and the second direction, and the first surface and the third surface being along the third direction; a laminate provided between the first surface region and the second surface region; Equipped with The laminate is a first magnetic layer; a second magnetic layer provided between the first magnetic layer and the second surface region; Including, the second magnetic layer includes a second magnetic layer surface facing the second surface region, the second surface further includes a third surface region; the first surface region is between the first surface and the third surface region; The third surface region is aligned along the second direction and the third direction, the fourth surface further includes a fourth surface region and a fifth surface region; a direction from the third surface region to the fourth surface region is along the first direction; The fourth surface region is aligned along the second direction and the third direction, a first distance along the first direction between the first surface region and the second surface region is shorter than a second distance along the first direction between the third surface region and the fourth surface region; the fifth surface region is between the second surface region and the fourth surface region; a plane including the fifth surface region intersects with a plane including the third surface region and a plane including the fourth surface region, the second magnetic pole has a first length along the second direction between the third surface and an intersection position of the plane including the fifth surface region and the plane including the fourth surface region, A magnetic head, wherein a ratio of a second length of the second magnetic layer surface along the second direction to the first length is not less than 0.1 and not more than 0.85.

[0112] (Configuration 7) 7. The magnetic head according to claim 6, wherein the length ratio is equal to or greater than 0.2 and equal to or less than 0.72.

[0113] (Configuration 8) 7. The magnetic head of claim 6, wherein the second direction is inclined with respect to the first direction.

[0114] (Configuration 9) 9. The magnetic head according to any one of configurations 1 to 8, wherein the laminate further includes a first non-magnetic layer provided between the first magnetic layer and the second magnetic layer.

[0115] (Configuration 10) 10. The magnetic head of claim 9, wherein the stack further includes a second non-magnetic layer provided between the first magnetic pole and the first magnetic layer.

[0116] (Configuration 11) 11. The magnetic head of claim 10, wherein the stack further includes a third non-magnetic layer disposed between the second magnetic layer and the second magnetic pole.

[0117] (Configuration 12) The laminate is a third magnetic layer provided between the first magnetic pole and the first magnetic layer; a fourth magnetic layer provided between the first magnetic layer and the second magnetic layer; a first non-magnetic layer provided between the first magnetic pole and the third magnetic layer; a second non-magnetic layer provided between the third magnetic layer and the first magnetic layer; a third non-magnetic layer provided between the first magnetic layer and the fourth magnetic layer; a fourth non-magnetic layer provided between the fourth magnetic layer and the second magnetic layer; a fifth non-magnetic layer provided between the second magnetic layer and the second magnetic pole; further comprising a first thickness of the first magnetic layer along the first direction is greater than a third thickness of the third magnetic layer along the first direction; The magnetic head according to any one of configurations 1 to 8, wherein a second thickness of the second magnetic layer along the first direction is greater than a fourth thickness of the fourth magnetic layer along the first direction.

[0118] (Configuration 13) the first nonmagnetic layer includes at least one selected from the group consisting of Ru, Ir, Ta, Rh, Pd, Pt, and W, the second nonmagnetic layer includes at least one selected from the group consisting of Cu, Au, Cr, Al, V, and Ag; the fifth nonmagnetic layer includes at least one selected from the group consisting of Cu, Au, Cr, Al, V, and Ag; 13. The magnetic head of claim 12, wherein the third non-magnetic layer includes at least one selected from the group consisting of Cu, Au, Cr, Al, V, and Ag, and the fourth non-magnetic layer includes at least one selected from the group consisting of Ru, Ir, Ta, Rh, Pd, Pt, and W, or the third non-magnetic layer includes at least one selected from the group consisting of Ru, Ir, Ta, Rh, Pd, Pt, and W, and the fourth non-magnetic layer includes at least one selected from the group consisting of Cu, Au, Cr, Al, V, and Ag.

[0119] (Configuration 14) The laminate is a third magnetic layer provided between the first magnetic layer and the second magnetic layer; a fourth magnetic layer provided between the second magnetic layer and the second magnetic pole; a first non-magnetic layer provided between the first magnetic pole and the first magnetic layer; a second non-magnetic layer provided between the first magnetic layer and the third magnetic layer; a third non-magnetic layer provided between the third magnetic layer and the second magnetic layer; a fourth non-magnetic layer provided between the second magnetic layer and the fourth magnetic layer; a fifth non-magnetic layer provided between the fourth magnetic layer and the second magnetic pole; further comprising a first thickness of the first magnetic layer along the first direction is greater than a third thickness of the third magnetic layer along the first direction; The magnetic head according to any one of configurations 1 to 8, wherein a second thickness of the second magnetic layer along the first direction is greater than a fourth thickness of the fourth magnetic layer along the first direction.

[0120] (Configuration 15) the first nonmagnetic layer includes at least one selected from the group consisting of Cu, Au, Cr, Al, V, and Ag; the fourth nonmagnetic layer includes at least one selected from the group consisting of Cu, Au, Cr, Al, V, and Ag; the fifth nonmagnetic layer includes at least one selected from the group consisting of Ru, Ir, Ta, Rh, Pd, Pt, and W, 13. The magnetic head of claim 12, wherein the second non-magnetic layer includes at least one selected from the group consisting of Ru, Ir, Ta, Rh, Pd, Pt, and W, and the third non-magnetic layer includes at least one selected from the group consisting of Cu, Au, Cr, Al, V, and Ag, or the second non-magnetic layer includes at least one selected from the group consisting of Cu, Au, Cr, Al, V, and Ag, and the third non-magnetic layer includes at least one selected from the group consisting of Ru, Ir, Ta, Rh, Pd, Pt, and W.

[0121] (Configuration 16) When a current flows through the laminate, an alternating magnetic field is generated from the laminate, and an alternating electric power is generated in the laminate; 16. The magnetic head according to any one of configurations 12 to 15, wherein the absolute value of the difference between the first frequency of the alternating magnetic field and the second frequency of the alternating power is 0.25 times or less the first frequency.

[0122] (Configuration 17) the first thickness is greater than the second thickness; At least a portion of the alternating power is generated in the second magnetic layer; 17. The magnetic head of claim 16, wherein at least a portion of the alternating magnetic field is generated from the first magnetic layer.

[0123] (Configuration 18) a magnetic head including a first magnetic pole, a second magnetic pole, and a laminate provided between the first magnetic pole and the second magnetic pole; an electric circuit capable of supplying current to the laminate; Equipped with The laminate is a first magnetic layer; a second magnetic layer provided between the first magnetic layer and the second magnetic pole; Including, The magnetic recording device wherein an alternating current is generated in the stack when the current flows through the stack.

[0124] (Configuration 19) When the current flows through the laminate, an alternating magnetic field is generated from the laminate, 19. The magnetic recording device according to configuration 18, wherein an absolute value of a difference between a first frequency of the alternating magnetic field and a second frequency of the alternating power is 0.25 times or less of the first frequency.

[0125] (Configuration 20) 20. The magnetic recording device of claim 19, wherein the first frequency is equal to or greater than 15 GHz and equal to or less than 50 GHz.

[0126] According to the embodiment, it is possible to provide a magnetic head and a magnetic recording device that can improve the recording density.

[0127] In this specification, "vertical" and "parallel" do not only mean strictly vertical and strictly parallel, but also include variations in the manufacturing process, and may mean substantially vertical and substantially parallel.

[0128] The embodiments of the present invention have been described above with reference to specific examples. However, the present invention is not limited to these specific examples. For example, the specific configurations of the elements included in the magnetic head, such as the magnetic pole, laminate, magnetic layer, non-magnetic layer, and wiring, are within 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 similar effects by appropriately selecting them from known ranges.

[0129] Any combination of two or more elements of each embodiment to the extent technically possible is also included within the scope of the present invention as long as it encompasses the gist of the present invention.

[0130] 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.

[0131] In addition, within the scope of the concept of the present invention, a person skilled in the art may come up with various modifications and alterations, and it will be understood that these modifications and alterations also fall within the scope of the present invention.

[0132] Although several 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 embodied 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 within the scope and spirit of the invention, and are also included in the scope of the invention and its equivalents as defined in the claims. [Explanation of symbols]

[0133] 20...Laminate, 20D...Electric circuit, 21-24...First to fourth magnetic layers, 21M, 22M...Magnetization, 30D...Recording circuit, 30F...Medium facing surface, 30c...Coil, 30i...Insulating portion, 31, 32...First and second magnetic poles, 33...Shield, 41-45...First to fifth non-magnetic layers, 60...Recording portion, 70...Reading portion, 71...Magnetic read 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, 110-112, 110a-110c...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 unit, 210...magnetic recording device, AR, AR1...arrows, D1 to D3...first to third directions, F1 to F4...first to fourth surfaces, Ha1...alternating magnetic field, Iw...recording current, L1 to L3...first to third lengths, P1...parameter, Pa1...alternating power, RL1...length ratio, Rw1...width ratio, T1, T2...first and second terminals, W1, W2...first and second wiring, d1, d2...first and second thicknesses, ic...electric current, je...electron current, r1 to r5...first to fifth surface regions, t1 to t4...first to fourth thicknesses, t41 to t45...first to fifth non-magnetic layer thicknesses, w1 to w3...first to third widths

Claims

1. a first magnetic pole including a first surface and a second surface intersecting the first surface, the second surface including a first surface region continuous with the first surface; a second magnetic pole, the second magnetic pole including a third surface and a fourth surface intersecting the third surface, the fourth surface including a second surface region, the second surface region being continuous with the third surface, a direction from the first surface region to the second surface region being along a first direction, the first surface region and the second surface region being along a second direction and a third direction, the third direction intersecting a plane including the first direction and the second direction, and the first surface and the third surface being along the third direction; a laminate provided between the first surface region and the second surface region; Equipped with The laminate is a first magnetic layer; a second magnetic layer provided between the first magnetic layer and the second surface region; Including, the second magnetic layer includes a second magnetic layer surface facing the second surface region, A magnetic head, wherein a width ratio of a second width of the second magnetic layer surface along the third direction to a first width of the first surface region along the third direction is 0.25 or more and 0.92 or less.

2. the second surface further includes a third surface region; the first surface region is between the first surface and the third surface region; the third surface region is aligned along the second direction and the third direction, the fourth surface further includes a fourth surface region and a fifth surface region; a direction from the third surface region to the fourth surface region is along the first direction; the fourth surface region is aligned along the second direction and the third direction, a first distance along the first direction between the first surface region and the second surface region is shorter than a second distance along the first direction between the third surface region and the fourth surface region; the fifth surface region is between the second surface region and the fourth surface region; a plane including the fifth surface region intersects with a plane including the third surface region and a plane including the fourth surface region; the second magnetic pole has a first length along the second direction between the third surface and an intersection position of the plane including the fifth surface region and the plane including the fourth surface region, 2. The magnetic head according to claim 1, wherein a ratio of a second length of the second magnetic layer surface along the second direction to the first length is equal to or greater than 0.1 and equal to or less than 0.

85.

3. The laminate is a third magnetic layer provided between the first magnetic pole and the first magnetic layer; a fourth magnetic layer provided between the first magnetic layer and the second magnetic layer; a first non-magnetic layer provided between the first magnetic pole and the third magnetic layer; a second non-magnetic layer provided between the third magnetic layer and the first magnetic layer; a third non-magnetic layer provided between the first magnetic layer and the fourth magnetic layer; a fourth non-magnetic layer provided between the fourth magnetic layer and the second magnetic layer; a fifth non-magnetic layer provided between the second magnetic layer and the second magnetic pole; further comprising a first thickness of the first magnetic layer along the first direction is greater than a third thickness of the third magnetic layer along the first direction; 3. The magnetic head according to claim 1, wherein a second thickness of the second magnetic layer along the first direction is greater than a fourth thickness of the fourth magnetic layer along the first direction.

4. the first nonmagnetic layer includes at least one selected from the group consisting of Ru, Ir, Ta, Rh, Pd, Pt, and W; the second nonmagnetic layer includes at least one selected from the group consisting of Cu, Au, Cr, Al, V, and Ag; the fifth nonmagnetic layer includes at least one selected from the group consisting of Cu, Au, Cr, Al, V, and Ag; 4. The magnetic head of claim 3, wherein the third non-magnetic layer includes at least one selected from the group consisting of Cu, Au, Cr, Al, V, and Ag, and the fourth non-magnetic layer includes at least one selected from the group consisting of Ru, Ir, Ta, Rh, Pd, Pt, and W, or the third non-magnetic layer includes at least one selected from the group consisting of Ru, Ir, Ta, Rh, Pd, Pt, and W, and the fourth non-magnetic layer includes at least one selected from the group consisting of Cu, Au, Cr, Al, V, and Ag.

5. The laminate is a third magnetic layer provided between the first magnetic layer and the second magnetic layer; a fourth magnetic layer provided between the second magnetic layer and the second magnetic pole; a first non-magnetic layer provided between the first magnetic pole and the first magnetic layer; a second non-magnetic layer provided between the first magnetic layer and the third magnetic layer; a third non-magnetic layer provided between the third magnetic layer and the second magnetic layer; a fourth non-magnetic layer provided between the second magnetic layer and the fourth magnetic layer; a fifth non-magnetic layer provided between the fourth magnetic layer and the second magnetic pole; further comprising a first thickness of the first magnetic layer along the first direction is greater than a third thickness of the third magnetic layer along the first direction; 3. The magnetic head according to claim 1, wherein a second thickness of the second magnetic layer along the first direction is greater than a fourth thickness of the fourth magnetic layer along the first direction.

6. the first nonmagnetic layer includes at least one selected from the group consisting of Cu, Au, Cr, Al, V, and Ag; the fourth nonmagnetic layer includes at least one selected from the group consisting of Cu, Au, Cr, Al, V, and Ag; the fifth nonmagnetic layer includes at least one selected from the group consisting of Ru, Ir, Ta, Rh, Pd, Pt, and W, 6. The magnetic head of claim 5, wherein the second non-magnetic layer includes at least one selected from the group consisting of Ru, Ir, Ta, Rh, Pd, Pt, and W, and the third non-magnetic layer includes at least one selected from the group consisting of Cu, Au, Cr, Al, V, and Ag, or the second non-magnetic layer includes at least one selected from the group consisting of Cu, Au, Cr, Al, V, and Ag, and the third non-magnetic layer includes at least one selected from the group consisting of Ru, Ir, Ta, Rh, Pd, Pt, and W.

7. When a current flows through the laminate, an alternating magnetic field is generated from the laminate, and an alternating electric power is generated in the laminate; 2. The magnetic head according to claim 1, wherein an absolute value of a difference between the first frequency of the alternating magnetic field and the second frequency of the alternating power is 0.25 times or less of the first frequency.

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