Magnetic recording apparatus

Abstract

The present disclosure provides a magnetic recording device capable of improving recording density. According to one embodiment, a magnetic recording apparatus includes a magnetic head and a magnetic recording medium. The magnetic head includes a first magnetic pole, a second magnetic pole, and a magnetic element provided between the first magnetic pole and the second magnetic pole. The magnetic element includes a first magnetic layer and a second magnetic layer. The magnetic element includes a midpoint between the first magnetic layer and the second magnetic layer in a first direction from the first magnetic pole toward the second magnetic pole. The first ratio (r1) and the second ratio (r2) satisfy-0.26 * r1 + 0.60 < = r2 < =-0.26 * r2 + 0.70. The first ratio (r1) is the ratio of a second distance (L2) between the first magnetic pole and the midpoint to a first distance (L1) between the first magnetic pole and the second magnetic pole. The second ratio (r2) is the ratio of the dynamic coercive force (Hc0) of the magnetic recording medium to the average anisotropic magnetic field (Hk).

Description

[0001] This application is based on Japanese Patent Application No. 2023-121861 (filing date July 26, 2023) and claims priority from this application. This application incorporates the entire contents of this application by reference. Technical Field

[0002] An embodiment of the present invention relates to a magnetic recording device. Background Art

[0003] Information is recorded on a magnetic recording medium such as a HDD (Hard Disk Drive) using a magnetic head. In magnetic recording devices, an improvement in recording density is desired. Summary of the invention

[0004] Embodiments of the present invention provide a magnetic recording device capable of improving recording density.

[0005] Technical solutions to solve problems

[0006] According to an embodiment, a magnetic recording device includes a magnetic head and a magnetic recording medium. The magnetic head includes a first magnetic pole, a second magnetic pole, and a magnetic element disposed between the first magnetic pole and the second magnetic pole. The magnetic element includes a first magnetic layer and a second magnetic layer disposed between the first magnetic layer and the second magnetic pole. The magnetic element includes a midpoint between the first magnetic layer and the second magnetic layer in a first direction from the first magnetic pole to the second magnetic pole. The first ratio r1 and the second ratio r2 satisfy -0.26×r1+0.60≤r2≤-0.26×r2+0.70. The first ratio r1 is a ratio of the second distance L2 to the first distance L1, the second distance L2 is a distance between the first magnetic pole and the midpoint in the first direction, and the first distance L1 is a distance between the first magnetic pole and the second magnetic pole in the first direction. The second ratio r2 is a ratio of the dynamic coercive force Hc0 of the magnetic recording medium to the average anisotropic magnetic field Hk of the magnetic recording medium.

[0007] According to the magnetic recording device having the above-described structure, it is possible to provide a magnetic recording device capable of improving recording density. BRIEF DESCRIPTION OF THE DRAWINGS

[0008] Figure 1 It is a schematic cross-sectional view illustrating the magnetic recording device according to the first embodiment.

[0009] Figure 2 This is a schematic cross-sectional view illustrating a part of the magnetic recording device according to the first embodiment.

[0010] Figure 3 It is a graph illustrating the characteristics of a magnetic recording device.

[0011] Figure 4 It is a graph illustrating the characteristics of a magnetic recording device.

[0012] Figure 5 It is a graph illustrating the characteristics of a magnetic recording device.

[0013] Figure 6 This is a schematic cross-sectional view illustrating a part of the magnetic recording device according to the first embodiment.

[0014] Figure 7 This is a schematic cross-sectional view illustrating a part of the magnetic recording device according to the first embodiment.

[0015] Figure 8 This is a schematic cross-sectional view illustrating a part of the magnetic recording device according to the first embodiment.

[0016] Fig. 9 This is a schematic cross-sectional view illustrating a part of the magnetic recording device according to the first embodiment.

[0017] Fig.10 It is a schematic perspective view illustrating a magnetic recording device according to an embodiment.

[0018] Fig.11 This is a schematic perspective view illustrating a part of the magnetic recording device according to the embodiment.

[0019] Fig.12 It is a schematic perspective view illustrating a magnetic recording device according to an embodiment.

[0020] Fig.13 (a) and Fig.13 (b) is a schematic perspective view illustrating a part of the magnetic recording device according to the embodiment.

[0021] Description of symbols

[0022] 20: magnetic element, 20D: element circuit, 21-24: 1st to 4th magnetic layers, 30D: recording circuit, 30F: medium facing surface, 30c: coil, 30i: insulating portion, 31, 32: 1st and 2nd magnetic poles, 33: shield, 41-45: 1st to 5th non-magnetic layers, 60: recording portion, 70: reproduction portion, 71: magnetic reproduction element, 72a, 72b: 1st and 2nd reproduction magnetic shield, 75: control portion, 80: magnetic recording medium, 81: magnetic recording layer, 82: medium substrate, 83: magnetization, 85: medium moving direction, 110-113: magnetic head, 150: magnetic recording device, 154: suspension, 155: arm, 156: voice coil motor, 157: bearing portion, 158: head gimbal assembly, 159: head slide block, 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: arrow, D1: first direction, Iw: recording current, L1, L2: first, second distance, P1: midpoint, T1, T2: first, second terminal, Tc1, Tc2: first, second coil terminal, V20: element voltage, W1, W2: first, second wiring, ic: element current, je: electron flow, r1, r2: first, second ratio, t1~t4: first to fourth magnetic layer thickness, t41~t45: first to fifth non-magnetic layer thickness DETAILED DESCRIPTION

[0023] (First embodiment)

[0024] Figure 1 It is a schematic cross-sectional view illustrating the magnetic recording device according to the first embodiment.

[0025] like Figure 1 As shown, the magnetic recording device 210 according to the embodiment includes a magnetic head 110 and a magnetic recording medium 80. The magnetic recording device 210 may also include a control unit 75. 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.

[0026] The magnetic head 110 includes a recording unit 60. As described later, the magnetic head 110 may also include a reproducing unit. The recording unit 60 includes a first magnetic pole 31, a second magnetic pole 32, and a magnetic element 20. The magnetic head 110 may include a coil 30c. The magnetic element 20 is provided between the first magnetic pole 31 and the second magnetic pole 32.

[0027] 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. Alternatively, the first magnetic pole 31 is a trailing shield and the second magnetic pole 32 is a main magnetic pole.

[0028] The direction from the magnetic recording medium 80 to the magnetic head 110 is set as the Z-axis direction. A direction perpendicular to the Z-axis direction is set as the X-axis direction. The direction perpendicular to the Z-axis direction and the X-axis direction is set 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. Along the down track direction, the magnetic recording medium 80 and the magnetic head 110 move relative to each other. A recording magnetic field generated by the magnetic head 110 is applied to a desired position of the magnetic recording medium 80. The magnetization of the desired position of the magnetic recording medium 80 is controlled to a direction corresponding to the recording magnetic field. Thus, information is recorded on the magnetic recording medium 80.

[0029] The direction from the first magnetic pole 31 to the second magnetic pole 32 is defined as the first direction D1. The first direction D1 may be substantially along the X-axis direction. In the embodiment, the first direction D1 may be inclined relative to the X-axis direction. The inclination angle may be, for example, greater than 0 degrees and less than 40 degrees.

[0030] 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 a side shield (not shown).

[0031] like Figure 1 As shown, a recording current Iw is supplied from a recording circuit 30D to the coil 30c. For example, a first coil terminal Tc1 and a second coil terminal Tc2 are provided on the coil 30c. The recording current Iw is supplied to the coil 30c via these coil terminals. A recording magnetic field corresponding to the recording current Iw is applied from the first magnetic pole 31 to the magnetic recording medium 80.

[0032] like Figure 1 As shown, the first magnetic pole 31 includes a medium facing surface 30F. The medium facing surface 30F is, for example, an ABS (Air Bearing Surface). The medium facing surface 30F faces, for example, the magnetic recording medium 80. The medium facing surface 30F is, for example, along the XY plane.

[0033] like Figure 1As shown, the element circuit 20D is electrically connected to the magnetic element 20. In this example, the magnetic element 20 is electrically connected to the first magnetic pole 31 and the second magnetic pole 32. The magnetic head 110 is provided with a first terminal T1 and a second terminal T2. The first terminal T1 is electrically connected to one end of the magnetic element 20 via the first wiring W1 and the first magnetic pole 31. The second terminal T2 is electrically connected to the other end of the magnetic element 20 via the second wiring W2 and the second magnetic pole 32. For example, an element current ic is supplied from the element circuit 20D to the magnetic element 20.

[0034] like Figure 1 As shown in FIG. 1 , the element current ic has a direction from the first magnetic pole 31 to the second magnetic pole 32. Figure 1 As shown, the electron current je accompanying the element current ic has a direction from the second magnetic pole 32 to the first magnetic pole 31. The element current ic includes a direct current component. The element current ic may be a direct current, for example.

[0035] For example, an element current ic above a threshold value flows in the magnetic element 20, generating oscillations in the magnetic layer included in the magnetic element 20. The magnetic element 20 functions as an STO (Spin-Torque Oscillator), for example. Along with the oscillations, an alternating magnetic field (for example, a high-frequency magnetic field) is generated from the magnetic element 20. The alternating magnetic field generated by the magnetic element 20 is applied to the magnetic recording medium 80 to assist in recording to the magnetic recording medium 80. For example, MAMR (Microwave Assisted Magnetic Recording) can be implemented. For example, the resistance of the magnetic element 20 vibrates corresponding to the alternating magnetic field from the magnetic element 20. The vibration of the resistance corresponds to the alternating magnetic field.

[0036] Oscillation of magnetization occurs in the first magnetic layer 21 and the second magnetic layer 22. These magnetic layers are, for example, oscillation layers.

[0037] The recording circuit 30D and the element circuit 20D are included in the control unit 75. The control unit 75 is electrically connected to the magnetic element 20 and the coil 30c. The control unit 75 is electrically connected to the first terminal T1, the second terminal T2 and the coil 30c. The control unit 75 can supply the recording current Iw to the coil 30c and the element current ic to the magnetic element 20.

[0038] For example, the control unit 75 (element circuit 20D) applies an element voltage V20 corresponding to the element current ic between the first terminal T1 and the second terminal T2. In practice, the element current ic can also be controlled by controlling the element voltage V20. During the recording operation, the control unit 75 applies the element voltage V20 between the first terminal T1 and the second terminal T2 while supplying the recording current Iw to the coil 30c.

[0039] Hereinafter, an example of the magnetic head 110 will be described.

[0040] Figure 2 This is a schematic cross-sectional view illustrating a part of the magnetic recording device according to the first embodiment.

[0041] like Figure 2 As shown, the magnetic element 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 magnetic pole 32. As will be described later, the magnetic element 20 may further include other magnetic layers.

[0042] The magnetic element 20 includes a midpoint P1 . The midpoint P1 is a midpoint between the first magnetic layer 21 and the second magnetic layer 22 in the first direction D1 from the first magnetic pole 31 to the second magnetic pole 32 .

[0043] The distance between the first magnetic pole 31 and the second magnetic pole 32 in the first direction D1 is set as the first distance L1. The distance between the first magnetic pole 31 and the midpoint P1 in the first direction D1 is set as the second distance L2. The first ratio r1 is the ratio of the second distance L2 to the first distance L1 (L2 / L1). The first ratio r1 is greater than 0 and less than 1.

[0044] The second ratio r2 is a ratio (Hc0 / Hk) of the dynamic coercive force Hc0 of the magnetic recording medium 80 to the average anisotropic magnetic field Hk of the magnetic recording medium 80. As described later, the magnetic recording medium 80 includes a magnetic recording layer 81. The dynamic coercive force Hc0 of the magnetic recording medium 80 may be the dynamic coercive force Hc0 of the magnetic recording layer 81. The average anisotropic magnetic field Hk of the magnetic recording medium 80 may be the average anisotropic magnetic field Hk of the magnetic recording layer 81. The dynamic coercive force Hc0 is, for example, a coercive force evaluated over a time of more than 1 ns and less than 10 ns. The time of more than 1 ns and less than 10 ns corresponds, for example, to the time from the start to the end of the reversal of magnetization in the magnetic recording device 210.

[0045] In the embodiment, the first ratio r1 and the second ratio r2 satisfy:

[0046] -0.26×r1+0.60≤r2≤-0.26×r2+0.70…(1).

[0047] When the above-mentioned first formula is satisfied, for example, a high SNR can be obtained. For example, at a high recording density, recording with a high SNR can be performed. A low error rate can also be maintained at a high recording density. According to the embodiment, a magnetic recording device capable of improving recording density can be provided.

[0048] The following is an example of simulation results on the characteristics of the magnetic recording device. In the following example, the first distance L1 is fixed and the second distance L2 is changed. In the following example, the first distance L1 is 27 nm. The magnetization volume of the first magnetic layer 21 is 16 nmT. The magnetization volume of the second magnetic layer 22 is 16 nmT. The average anisotropic magnetic field Hk is set constant and the dynamic coercive force Hc0 is changed. The average anisotropic magnetic field Hk is 19400 kOe.

[0049] Figure 3 and Figure 4 It is a graph illustrating the characteristics of a magnetic recording device.

[0050] In these figures, the horizontal axis is the second ratio r2. The vertical axis is SNR. For SNR, the output S of the reproduced signal and the output N of the noise are used to calculate the SNR by 20log 10 (S / N) is used to define the Figure 3 In the example, the first ratio r1 is 0.5. Figure 4 , the first ratio r1 is 0.7.

[0051] like Figure 3 As shown, when the first ratio r1 is 0.5, the SNR is high when the second ratio r2 is about 0.54. When the second ratio r2 is less than 0.54, the SNR increases as the second ratio r2 increases. When the second ratio r2 is higher than 0.54, the SNR decreases as the second ratio r2 increases.

[0052] like Figure 4 As shown, when the first ratio r1 is 0.7, the SNR is high when the second ratio r2 is about 0.44. When the second ratio r2 is less than 0.44, the SNR increases as the second ratio r2 increases. When the second ratio r2 is higher than 0.44, the SNR decreases as the second ratio r2 increases.

[0053] In this way, the second ratio r2 that can obtain a high SNR changes according to the value of the first ratio r1. When the SNR is 9.0 or more, recording can be performed at a practically high density.

[0054] Figure 5 It is a graph illustrating the characteristics of a magnetic recording device.

[0055] exist Figure 5 In the figure, the horizontal axis is the first ratio r1. The vertical axis is the second ratio r2. Figure 5 In the figure, black dots indicate that an SNR of 0.75 or higher can be obtained. White dots indicate that the SNR is less than 0.75. Figure 5 As shown in Figure 2, the conditions for obtaining an SNR of 9.0 or above (black dots) are given by

[0056] r2=-0.2612×r1+0.6493…(2)

[0057] express.

[0058] A high SNR can be obtained when the formula 2 is satisfied. When an error of 0.5 is considered in the relationship of the formula 2, the relationship of the above-mentioned formula 1 can be obtained. In practice, a high SNR can be obtained when the formula 1 is satisfied.

[0059] For example, the recording magnetic field generated from the first magnetic pole 31 is applied to the magnetic recording medium 80, and acts on the magnetization of the magnetic recording medium 80. On the other hand, the alternating magnetic field generated from the magnetic element 20 is applied to the magnetic recording medium 80. When the dynamic coercive force Hc0 of the magnetic recording medium 80 is considered, it can be considered that there is an appropriate relationship between the position where the recording magnetic field substantially affects the magnetization of the magnetic recording medium 80 and the position of the midpoint P1 of the two oscillation layers. When the above-mentioned first formula is satisfied, it can be considered that the alternating magnetic field generated from the magnetic element 20 is appropriately applied to the position where the recording magnetic field substantially affects the magnetization of the magnetic recording medium 80. Therefore, it can be considered that when the first formula is satisfied, a high SNR can be obtained.

[0060] In the embodiment, the first ratio r1 is preferably, for example, not less than 0.35 and not more than 0.7. In this case, it is easy to stably obtain an alternating magnetic field with high efficiency.

[0061] In the embodiment, the second ratio r2 is preferably, for example, not less than 0.45 and not more than 0.56. In this case, it is easy to obtain a magnetic recording medium 80 having stable characteristics. It is easy to obtain stable characteristics.

[0062] In the embodiment, the average anisotropic magnetic field Hk is preferably 17300 Oe or more and 21200 Oe or less. The dynamic coercive force Hc0 is preferably 7500 Oe or more and 11000 Oe or less. A magnetic recording medium 80 having stable characteristics can be obtained.

[0063] In the embodiment, the first distance L1 is preferably, for example, not less than 15 nm and not more than 50 nm. A high-intensity alternating magnetic field can be stably obtained.

[0064] In the embodiment, the product of the first saturation magnetization of the first magnetic layer 21 and the thickness of the first magnetic layer 21 in the first direction D1 (the first magnetic layer thickness t1 described later) is preferably 9 nmT or more and 19 nmT or less. The product of the second saturation magnetization of the second magnetic layer 22 and the thickness of the second magnetic layer 22 in the first direction D1 (the second magnetic layer thickness t2 described later) is preferably 9 nmT or more and 19 nmT or less. Stable oscillation is easily obtained. A stable alternating magnetic field can be obtained.

[0065] Figure 6 and Figure 7 This is a schematic cross-sectional view illustrating a part of the magnetic recording device according to the first embodiment.

[0066] like Figure 6 As shown, in the magnetic head 111 included in the magnetic recording device 210 according to the embodiment, the magnetic element 20 includes the third magnetic layer 23 and the fourth magnetic layer 24. Except for this, the structure of the magnetic head 111 may be the same as that of the magnetic head 110.

[0067] In the magnetic head 111, the magnetic element 20 includes a first magnetic layer 21, a second magnetic layer 22, a third magnetic layer 23, and a fourth magnetic layer 24. As already described, the second magnetic layer 22 is disposed between the first magnetic layer 21 and the second magnetic pole 32. The third magnetic layer 23 is disposed between the first magnetic pole 31 and the first magnetic layer 21. The fourth magnetic layer 24 is disposed between the first magnetic layer 21 and the second magnetic layer 22.

[0068] like Figure 7 As shown, the thickness of the first magnetic layer 21 along the first direction D1 is set as the first magnetic layer thickness t1. The thickness of the second magnetic layer 22 along the first direction D1 is set as the second magnetic layer thickness t2. The thickness of the third magnetic layer 23 along the first direction D1 is set as the third magnetic layer thickness t3. The thickness of the fourth magnetic layer 24 along the first direction D1 is set as the fourth magnetic layer thickness t4.

[0069] In the embodiment, the first magnetic layer thickness t1 is thicker than the third magnetic layer thickness t3. The second magnetic layer thickness t2 is thicker than the fourth magnetic layer thickness t4. The first magnetic layer thickness t1 is thicker than the fourth magnetic layer thickness t4. The second magnetic layer thickness t2 is thicker than the third magnetic layer thickness t3.

[0070] For example, the first magnetic layer 21 and the second magnetic layer 22 function as oscillation layers, and the third magnetic layer 23 and the fourth magnetic layer 24 function as spin injection layers.

[0071] The magnetic element 20 may include, for example, a first nonmagnetic layer 41, a second nonmagnetic layer 42, a third nonmagnetic layer 43, a fourth nonmagnetic layer 44, and a fifth nonmagnetic layer 45. The first nonmagnetic layer 41 is disposed between the first magnetic layer 21 and the fourth magnetic layer 24. The second nonmagnetic layer 42 is disposed between the fourth magnetic layer 24 and the second magnetic layer 22. The third nonmagnetic layer 43 is disposed between the first magnetic pole 31 and the third magnetic layer 23. The fourth nonmagnetic layer 44 is disposed between the third magnetic layer 23 and the first magnetic layer 21. The fifth nonmagnetic layer 45 is disposed between the second magnetic layer 22 and the second magnetic pole 32.

[0072] In the magnetic head 111, the first nonmagnetic layer 41 is in contact with the first magnetic layer 21 and the fourth magnetic layer 24. The second nonmagnetic layer 42 is in contact with the fourth magnetic layer 24 and the second magnetic layer 22. The third nonmagnetic layer 43 is in contact with the first magnetic pole 31 and the third magnetic layer 23. The fourth nonmagnetic layer 44 is in contact with the third magnetic layer 23 and the first magnetic layer 21. The fifth nonmagnetic layer 45 is in contact with the second magnetic layer 22 and the second magnetic pole 32.

[0073] In the magnetic head 111, the magnetic element 20 also includes a midpoint P1 (see Figure 6 ). The relationship of the first formula is also satisfied in the magnetic head 111. Thus, a high SNR can be obtained.

[0074] In the magnetic head 111, the first magnetic layer thickness t1 is preferably, for example, greater than 5 nm and less than 15 nm. The second magnetic layer thickness t2 is preferably, for example, greater than 5 nm and less than 15 nm. The third magnetic layer thickness t3 is preferably, for example, greater than 1 nm and less than 5 nm. The fourth magnetic layer thickness t4 is preferably, for example, greater than 1 nm and less than 5 nm. A stable alternating magnetic field is easily obtained.

[0075] In the magnetic head 111, the product of the first saturation magnetization of the first magnetic layer 21 and the first magnetic layer thickness t1 is preferably 9 nmT or more and 19 nmT or less. The product of the second saturation magnetization of the second magnetic layer 22 and the second magnetic layer thickness t2 is preferably 9 nmT or more and 19 nmT or less. The product of the third saturation magnetization of the third magnetic layer 23 and the third magnetic layer thickness t3 is preferably 2 nmT or more and 10 nmT or less. The product of the fourth saturation magnetization of the fourth magnetic layer 24 and the fourth magnetic layer thickness t4 is preferably 2 nmT or more and 10 nmT or less. For example, a stable alternating magnetic field can be obtained with high efficiency.

[0076] exist Figure 2 In the illustrated magnetic head 110, a nonmagnetic layer corresponding to at least any one of the first nonmagnetic layer 41 and the second nonmagnetic layer 42 may be provided between the first magnetic layer 21 and the second magnetic layer 22. In the magnetic head 110, a nonmagnetic layer corresponding to at least any one of the third nonmagnetic layer 43 and the fourth nonmagnetic layer 44 may be provided between the first magnetic pole 31 and the second magnetic layer 22. In the magnetic head 110, a nonmagnetic layer corresponding to the fifth nonmagnetic layer 45 may be provided between the second magnetic layer 22 and the second magnetic pole 32.

[0077] In the magnetic head 111,

[0078] The first nonmagnetic layer 41 includes at least one selected from the group consisting of Cu, Au, Cr, Al, V, and Ag.

[0079] The second nonmagnetic layer 42 includes at least one selected from the group consisting of Cu, Au, Cr, Al, V, and Ag.

[0080] The third nonmagnetic layer 43 includes at least one selected from the group consisting of Cu, Au, Cr, Al, V, and Ag.

[0081] The fourth nonmagnetic layer 44 includes at least one selected from the group consisting of Ru, Ir, Ta, Rh, Pd, Pt, and W.

[0082] The fifth nonmagnetic layer 45 includes at least one selected from Ru, Ir, Ta, Rh, Pd, Pt, and W. Thus, a stable alternating magnetic field can be easily obtained.

[0083] like Figure 7 As shown, the first non-magnetic layer 41 has a first non-magnetic layer thickness t41 along the first direction D1. The first non-magnetic layer thickness t41 is preferably, for example, greater than 0.5 nm and less than 6 nm. The second non-magnetic layer thickness t42 is preferably, for example, greater than 0.5 nm and less than 6 nm. The third non-magnetic layer thickness t43 is preferably, for example, greater than 0.5 nm and less than 6 nm. The fourth non-magnetic layer thickness t44 is preferably, for example, greater than 0.5 nm and less than 6 nm. The fifth non-magnetic layer thickness t45 is preferably, for example, greater than 0.5 nm and less than 6 nm. It is easy to obtain a stable alternating magnetic field.

[0084] like Figure 6 As shown in FIG. 1 , the first direction D1 in the magnetic head 111 is inclined relative to the X-axis direction. Figure 6 As shown, the magnetic head 110 includes a medium facing surface 30F. The angle between the first direction D1 and the medium facing surface 30F may be greater than 0 degrees and less than 40 degrees.

[0085] Figure 8 This is a schematic cross-sectional view illustrating a part of the magnetic recording device according to the first embodiment.

[0086] like Figure 8 As shown, in the magnetic head 112 included in the magnetic recording device 210 according to the embodiment, the material of the nonmagnetic layer included in the magnetic element 20 is different from the material of the nonmagnetic layer included in the magnetic head 111. Otherwise, the structure of the magnetic head 112 may be the same as that of the magnetic head 111.

[0087] In the magnetic head 112,

[0088] The first nonmagnetic layer 41 includes at least one selected from the group consisting of Ru, Ir, Ta, Rh, Pd, Pt, and W.

[0089] The second nonmagnetic layer 42 includes at least one selected from the group consisting of Cu, Au, Cr, Al, V, and Ag.

[0090] The third nonmagnetic layer 43 includes at least one selected from the group consisting of Cu, Au, Cr, Al, V, and Ag.

[0091] The fourth nonmagnetic layer 44 includes at least one selected from the group consisting of Cu, Au, Cr, Al, V, and Ag.

[0092] The fifth nonmagnetic layer 45 includes at least one selected from Ru, Ir, Ta, Rh, Pd, Pt and W. Thus, a stable alternating magnetic field can be easily obtained. The relationship of the above-mentioned first formula is also satisfied in the magnetic head 112. A high SNR can be obtained.

[0093] Fig. 9 This is a schematic cross-sectional view illustrating a part of the magnetic recording device according to the first embodiment.

[0094] like Fig. 9 As shown, in the magnetic head 113 included in the magnetic recording device 210 according to the embodiment, the material of the nonmagnetic layer included in the magnetic element 20 is different from the material of the nonmagnetic layer included in the magnetic head 111. Otherwise, the structure of the magnetic head 113 may be the same as that of the magnetic head 111.

[0095] In the magnetic head 113,

[0096] The first nonmagnetic layer 41 includes at least one selected from the group consisting of Ru, Ir, Ta, Rh, Pd, Pt, and W.

[0097] The second nonmagnetic layer 42 includes at least one selected from the group consisting of Cu, Au, Cr, Al, V, and Ag.

[0098] The third nonmagnetic layer 43 includes at least one selected from the group consisting of Ru, Ir, Ta, Rh, Pd, Pt, and W.

[0099] The fourth nonmagnetic layer 44 includes at least one selected from the group consisting of Cu, Au, Cr, Al, V, and Ag.

[0100] The fifth nonmagnetic layer 45 includes at least one selected from Ru, Ir, Ta, Rh, Pd, Pt and W. Thus, a stable alternating magnetic field can be easily obtained. The relationship of the above-mentioned first formula is also satisfied in the magnetic head 113. A high SNR can be obtained.

[0101] Hereinafter, examples of other configurations related to the magnetic recording device according to the embodiment will be described.

[0102] Fig.10 It is a schematic perspective view illustrating a magnetic recording device according to an embodiment.

[0103] like Fig.10As shown, the magnetic head (e.g., magnetic head 110) according to the embodiment is used together with the magnetic recording medium 80. In this example, the magnetic head 110 includes a recording unit 60 and a reproducing unit 70. Information is recorded on the magnetic recording medium 80 by the recording unit 60 of the magnetic head 110. Information recorded on the magnetic recording medium 80 is reproduced by the reproducing unit 70.

[0104] The magnetic recording medium 80 includes, for example, a dielectric substrate 82 and a magnetic recording layer 81 provided on the dielectric substrate 82. The magnetization 83 of the magnetic recording layer 81 is controlled by the recording unit 60.

[0105] In the embodiment, the thickness of the magnetic recording layer 81 may be, for example, 5 nm or more and 50 nm or less. It is easy to obtain a magnetic recording layer 81 having stable characteristics. The magnetic recording layer 81 may be, for example, a perpendicular magnetization film.

[0106] The reproduction unit 70 includes, for example, a first reproduction magnetic shield 72a, a second reproduction magnetic shield 72b, and a magnetic reproduction element 71. The magnetic reproduction element 71 is provided between the first reproduction magnetic shield 72a and the second reproduction magnetic shield 72b. The magnetic reproduction element 71 can output a signal corresponding to the magnetization 83 of the magnetic recording layer 81.

[0107] like Fig.10 As shown, the magnetic recording medium 80 moves relative to the magnetic head 110 in the medium moving direction 85. The magnetic head 110 controls information corresponding to the magnetization 83 of the magnetic recording layer 81 at any position. The magnetic head 110 reproduces information corresponding to the magnetization 83 of the magnetic recording layer 81 at any position.

[0108] Fig.11 This is a schematic perspective view illustrating a part of the magnetic recording device according to the embodiment.

[0109] Fig.11 A head slider is illustrated.

[0110] The magnetic head 110 is provided on a head slider 159. The head slider 159 is made of, for example, Al2O3 / TiC, etc. The head slider 159 moves relative to the magnetic recording medium while floating on or contacting the magnetic recording medium.

[0111] The head slider 159 has, for example, an air inlet side 159A and an air outlet side 159B. The magnetic head 110 is disposed on the side of the air outlet side 159B of the head slider 159. Thus, the magnetic head 110 moves relative to the magnetic recording medium while floating or contacting the magnetic recording medium.

[0112] Fig.12 It is a schematic perspective view illustrating a magnetic recording device according to an embodiment.

[0113] Fig.13(a) and Fig.13 (b) is a schematic perspective view illustrating a part of the magnetic recording device according to the embodiment.

[0114] like Fig.12 As shown, in the magnetic recording device 150 involved in the embodiment, a rotary actuator is used. The recording medium disk 180 is assembled on the 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 the control signal from the drive device control unit. The magnetic recording device 150 involved in this embodiment may also have 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). 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 also be a hybrid HDD (Hard Disk Drive).

[0115] The head slider 159 records and reproduces information recorded on the recording medium disk 180. The head slider 159 is provided at the front end of the thin film suspension 154. The magnetic head according to the embodiment is provided near the front end of the head slider 159.

[0116] When the recording medium disk 180 rotates, the pressing pressure by the suspension 154 is balanced with the pressure generated on the medium facing surface (ABS) of the head slider 159. The distance between the medium facing surface of the head slider 159 and the surface of the recording medium disk 180 becomes a predetermined floating amount. In the embodiment, the head slider 159 may also contact the recording medium disk 180. For example, a contact movement type may also be applied.

[0117] 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, etc. 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 magnetic yoke. A drive coil is provided between the permanent magnet and the opposing magnetic 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.

[0118] The arm 155 is held by a ball bearing. The ball bearings are provided at two locations, upper and lower, of the bearing portion 157. The arm 155 can be rotated and slid by the voice coil motor 156. The magnetic head can be moved to any position of the recording medium disk 180.

[0119] Fig.13(a) illustrates a partial configuration of the magnetic recording device and is an enlarged perspective view of the head stack assembly 160 .

[0120] Fig.13 (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 .

[0121] like Fig.13 As shown in (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 direction in which the support frame 161 extends is opposite to the direction in which the head gimbal assembly 158 extends. The support frame 161 supports the coil 162 of the voice coil motor 156.

[0122] like Fig.13 As shown in FIG. 1 ( b ), the head gimbal assembly 158 includes an arm 155 extending from a bearing portion 157 and a suspension 154 extending from the arm 155 .

[0123] A head slider 159 is provided at the front end of the suspension 154. The head slider 159 is provided with the magnetic head according to the embodiment.

[0124] The head assembly (head gimbal assembly) 158 according to the embodiment includes the 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.

[0125] The suspension 154 may include, for example, leads (not shown) for recording and reproducing signals. The suspension 154 may also include, for example, leads (not shown) for a heater for adjusting the floating amount. The suspension 154 may also include, for example, leads (not shown) for an oscillating element, etc. These leads are electrically connected to a plurality of electrodes provided on the magnetic head.

[0126] 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 the magnetic recording medium. In the signal processing unit 190, the input and 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.

[0127] The magnetic recording device 150 according to the embodiment includes a magnetic recording medium, a magnetic head according to the embodiment, a movable part, a position control part, and a signal processing part. The movable part is configured to enable the magnetic recording medium and the magnetic head to move relatively in a separated or contacted state. The position control part positions the magnetic head at a predetermined recording position of the magnetic recording medium. The signal processing part performs recording and reproduction of signals to the magnetic recording medium using the magnetic head.

[0128] For example, as the magnetic recording medium, a recording medium disk 180 is used. The movable portion includes, for example, a head slider 159. The position control portion includes, for example, a head gimbal assembly 158.

[0129] The implementation method may include the following technical solutions.

[0130] (Technical Solution 1)

[0131] A magnetic recording device comprising:

[0132] Magnetic heads; and

[0133] Magnetic recording media,

[0134] The magnetic head comprises:

[0135] 1st magnetic pole;

[0136] a second magnetic pole; and

[0137] a magnetic element disposed between the first magnetic pole and the second magnetic pole,

[0138] The magnetic element comprises:

[0139] a first magnetic layer; and

[0140] a second magnetic layer disposed between the first magnetic layer and the second magnetic pole,

[0141] The magnetic element includes a midpoint between the first magnetic layer and the second magnetic layer in a first direction from the first magnetic pole to the second magnetic pole,

[0142] The first ratio r1 and the second ratio r2 satisfy:

[0143] -0.26×r1+0.60≤r2≤-0.26×r2+0.70,

[0144] The first ratio r1 is a ratio of the second distance L2 to the first distance L1, the second distance L2 is the distance between the first magnetic pole and the midpoint in the first direction, and the first distance L1 is the distance between the first magnetic pole and the second magnetic pole in the first direction.

[0145] The second ratio r2 is a ratio of the dynamic coercive force Hc0 of the magnetic recording medium to the average anisotropic magnetic field Hk of the magnetic recording medium.

[0146] (Technical Solution 2)

[0147] According to the magnetic recording device described in technical solution 1,

[0148] The magnetic element further comprises:

[0149] a third magnetic layer disposed between the first magnetic pole and the first magnetic layer; and

[0150] a fourth magnetic layer disposed between the first magnetic layer and the second magnetic layer,

[0151] A first magnetic layer thickness of the first magnetic layer along the first direction is thicker than a third magnetic layer thickness of the third magnetic layer along the first direction.

[0152] A second magnetic layer thickness of the second magnetic layer along the first direction is thicker than a fourth magnetic layer thickness of the fourth magnetic layer along the first direction.

[0153] (Technical Solution 3)

[0154] According to the magnetic recording device described in technical solution 2,

[0155] The first magnetic layer is thicker than the fourth magnetic layer.

[0156] The second magnetic layer is thicker than the third magnetic layer.

[0157] (Technical Solution 4)

[0158] According to the magnetic recording device described in technical solution 2,

[0159] The magnetic element further comprises:

[0160] a first non-magnetic layer disposed between the first magnetic layer and the fourth magnetic layer;

[0161] a second non-magnetic layer disposed between the fourth magnetic layer and the second magnetic layer;

[0162] a third non-magnetic layer disposed between the first magnetic pole and the third magnetic layer;

[0163] a fourth non-magnetic layer disposed between the third magnetic layer and the first magnetic layer; and

[0164] A fifth non-magnetic layer is provided between the second magnetic layer and the second magnetic pole.

[0165] (Technical Solution 5)

[0166] According to the magnetic recording device described in technical solution 4,

[0167] The first non-magnetic layer is in contact with the first magnetic layer and the fourth magnetic layer.

[0168] The second non-magnetic layer is in contact with the fourth magnetic layer and the second magnetic layer.

[0169] The third non-magnetic layer is in contact with the first magnetic pole and the third magnetic layer.

[0170] The fourth non-magnetic layer is in contact with the third magnetic layer and the first magnetic layer.

[0171] The fifth non-magnetic layer is in contact with the second magnetic layer and the second magnetic pole.

[0172] (Technical Solution 6)

[0173] According to the magnetic recording device described in technical solution 4 or 5,

[0174] The first non-magnetic layer includes at least one selected from Cu, Au, Cr, Al, V and Ag.

[0175] The second non-magnetic layer includes at least one selected from Cu, Au, Cr, Al, V and Ag.

[0176] The third non-magnetic layer includes at least one selected from Cu, Au, Cr, Al, V and Ag.

[0177] The fourth non-magnetic layer includes at least one selected from Ru, Ir, Ta, Rh, Pd, Pt and W,

[0178] The fifth non-magnetic layer includes at least one selected from Ru, Ir, Ta, Rh, Pd, Pt, and W.

[0179] (Technical Solution 7)

[0180] According to the magnetic recording device described in technical solution 4 or 5,

[0181] The first non-magnetic layer includes at least one selected from Ru, Ir, Ta, Rh, Pd, Pt and W.

[0182] The second non-magnetic layer includes at least one selected from Cu, Au, Cr, Al, V and Ag.

[0183] The third non-magnetic layer includes at least one selected from Cu, Au, Cr, Al, V and Ag.

[0184] The fourth non-magnetic layer includes at least one selected from Cu, Au, Cr, Al, V and Ag.

[0185] The fifth non-magnetic layer includes at least one selected from Ru, Ir, Ta, Rh, Pd, Pt, and W.

[0186] (Technical Solution 8)

[0187] According to the magnetic recording device described in technical solution 4 or 5,

[0188] The first non-magnetic layer includes at least one selected from Ru, Ir, Ta, Rh, Pd, Pt and W.

[0189] The second non-magnetic layer includes at least one selected from Cu, Au, Cr, Al, V and Ag.

[0190] The third non-magnetic layer includes at least one selected from Ru, Ir, Ta, Rh, Pd, Pt and W.

[0191] The fourth non-magnetic layer includes at least one selected from Cu, Au, Cr, Al, V and Ag.

[0192] The fifth non-magnetic layer includes at least one selected from Ru, Ir, Ta, Rh, Pd, Pt, and W.

[0193] (Technical Solution 9)

[0194] The magnetic recording device according to any one of technical solutions 1 to 8,

[0195] The first ratio r1 is greater than or equal to 0.35 and less than or equal to 0.7.

[0196] (Technical Solution 10)

[0197] The magnetic recording device according to any one of technical solutions 1 to 9,

[0198] The second ratio r2 is greater than or equal to 0.45 and less than or equal to 0.56.

[0199] (Technical Solution 11)

[0200] According to the magnetic recording device described in technical solution 1,

[0201] a product of a first saturation magnetization of the first magnetic layer and a first magnetic layer thickness of the first magnetic layer in the first direction is 9 nmT or more and 19 nmT or less,

[0202] A product of a second saturation magnetization of the second magnetic layer and a second magnetic layer thickness of the second magnetic layer in the first direction is greater than or equal to 9 nmT and less than or equal to 19 nmT.

[0203] (Technical Solution 12)

[0204] According to the magnetic recording device described in technical solution 2 or 3,

[0205] The product of the first saturation magnetization of the first magnetic layer and the thickness of the first magnetic layer is 9 nmT or more and 19 nmT or less,

[0206] The product of the second saturation magnetization of the second magnetic layer and the thickness of the second magnetic layer is greater than or equal to 9 nmT and less than or equal to 19 nmT.

[0207] The product of the third saturation magnetization of the third magnetic layer and the thickness of the third magnetic layer is greater than or equal to 2 nmT and less than or equal to 10 nmT.

[0208] A product of a fourth saturation magnetization of the fourth magnetic layer and a thickness of the fourth magnetic layer is greater than or equal to 2 nmT and less than or equal to 10 nmT.

[0209] (Technical Solution 13)

[0210] The magnetic recording device according to any one of technical solutions 1 to 12,

[0211] The average anisotropic magnetic field Hk is greater than or equal to 17300 Oe and less than or equal to 21200 Oe,

[0212] The dynamic coercive force Hc0 is greater than or equal to 7500 Oe and less than or equal to 11000 Oe.

[0213] (Technical Solution 14)

[0214] The magnetic recording device according to any one of technical solutions 1 to 13,

[0215] The first distance L1 is greater than or equal to 15 nm and less than or equal to 50 nm.

[0216] (Technical Solution 15)

[0217] According to the magnetic recording device described in technical solution 2 or 3,

[0218] The thickness of the first magnetic layer is greater than or equal to 5 nm and less than or equal to 15 nm.

[0219] The second magnetic layer has a thickness of 5 nm or more and 15 nm or less.

[0220] The thickness of the third magnetic layer is not less than 1 nm and not more than 5 nm.

[0221] The fourth magnetic layer has a thickness of not less than 1 nm and not more than 5 nm.

[0222] (Technical Solution 16)

[0223] The magnetic recording device according to any one of technical solutions 1 to 15,

[0224] The magnetic recording medium comprises a magnetic recording layer,

[0225] The magnetic recording layer has a thickness of 5 nm to 50 nm.

[0226] (Technical Solution 17)

[0227] According to the magnetic recording device described in technical solution 16,

[0228] The magnetic recording layer is a perpendicular magnetization film.

[0229] (Technical Solution 18)

[0230] The magnetic recording device according to any one of technical solutions 1 to 16,

[0231] The magnetic head includes a medium-opposing surface,

[0232] An angle between the first direction and the medium-facing surface is greater than or equal to 0 degrees and less than or equal to 40 degrees.

[0233] (Technical Solution 19)

[0234] The magnetic recording device according to any one of technical solutions 1 to 18,

[0235] It also has component circuits,

[0236] The element circuit can supply an element current having a direction from the first magnetic layer to the second magnetic layer to the magnetic element.

[0237] When the element current is supplied to the magnetic element, an alternating magnetic field is generated from the magnetic element.

[0238] (Technical Solution 20)

[0239] The magnetic recording device according to any one of technical solutions 1 to 19,

[0240] It also has a recording circuit.

[0241] The magnetic head further comprises a coil,

[0242] The recording circuit is capable of supplying a recording current to the coil,

[0243] Information corresponding to the recording current is recorded on the magnetic recording medium.

[0244] According to the embodiment, it is possible to provide a magnetic recording device capable of improving recording density.

[0245] In the present application specification, “perpendicular” and “parallel” do not only mean strictly perpendicular and strictly parallel, but also include, for example, deviations in the manufacturing process, as long as they are substantially perpendicular and substantially parallel.

[0246] The embodiments of the present invention are described above with reference to specific examples. However, the present invention is not limited to these specific examples. For example, the specific configuration of each element such as the magnetic pole, magnetic element, magnetic layer, non-magnetic layer and control unit included in the magnetic head and magnetic recording device is included in the scope of the present invention as long as those skilled in the art can implement the present invention in the same manner and obtain the same effect by appropriately selecting from the known range.

[0247] Any combination of two or more elements in each specific example within a technically possible range is also included in the scope of the present invention as long as it includes the gist of the present invention.

[0248] In addition, as an embodiment of the present invention, all magnetic recording devices that can be implemented by those skilled in the art by making appropriate design changes based on the above-mentioned magnetic recording device also belong to the scope of the present invention as long as they include the spirit of the present invention.

[0249] Furthermore, within the scope of the concept of the present invention, a person skilled in the art will be able to conceive of various changes and modifications, and it should be understood that these changes and modifications also belong to the scope of the present invention.

[0250] Some embodiments of the present invention are described above, but these embodiments are provided as examples and are not intended to limit the scope of the invention. These new embodiments can be implemented in various other ways, and various omissions, substitutions, and changes can be made without departing from the scope of the purpose of the invention. These embodiments and / or their variations are included in the scope and / or purpose of the invention, and are included in the invention described in the claims and the scope of their equivalents.

Claims

1. A magnetic recording device comprising: magnetic head; and Magnetic recording media, The magnetic head comprises: 1st magnetic pole; a second magnetic pole; and a magnetic element disposed between the first magnetic pole and the second magnetic pole, The magnetic element comprises: a first magnetic layer; and a second magnetic layer disposed between the first magnetic layer and the second magnetic pole, The magnetic element includes a midpoint between the first magnetic layer and the second magnetic layer in a first direction from the first magnetic pole to the second magnetic pole, The first ratio r1 and the second ratio r2 satisfy: -0.26×r1+0.60≤r2≤-0.26×r2+0.70， The first ratio r1 is a ratio of the second distance L2 to the first distance L1, the second distance L2 is the distance between the first magnetic pole and the midpoint in the first direction, and the first distance L1 is the distance between the first magnetic pole and the second magnetic pole in the first direction. The second ratio r2 is a ratio of the dynamic coercive force Hc0 of the magnetic recording medium to the average anisotropic magnetic field Hk of the magnetic recording medium.

2. The magnetic recording device according to claim 1, The magnetic element further comprises: a third magnetic layer disposed between the first magnetic pole and the first magnetic layer; and a fourth magnetic layer disposed between the first magnetic layer and the second magnetic layer, A first magnetic layer thickness of the first magnetic layer along the first direction is thicker than a third magnetic layer thickness of the third magnetic layer along the first direction. A second magnetic layer thickness of the second magnetic layer along the first direction is thicker than a fourth magnetic layer thickness of the fourth magnetic layer along the first direction.

3. The magnetic recording device according to claim 2, The magnetic element further comprises: a first non-magnetic layer disposed between the first magnetic layer and the fourth magnetic layer; a second non-magnetic layer disposed between the fourth magnetic layer and the second magnetic layer; a third non-magnetic layer disposed between the first magnetic pole and the third magnetic layer; a fourth non-magnetic layer disposed between the third magnetic layer and the first magnetic layer; and A fifth non-magnetic layer is provided between the second magnetic layer and the second magnetic pole.

4. The magnetic recording device according to claim 3, The first non-magnetic layer is in contact with the first magnetic layer and the fourth magnetic layer. The second non-magnetic layer is in contact with the fourth magnetic layer and the second magnetic layer. The third non-magnetic layer is in contact with the first magnetic pole and the third magnetic layer. The fourth non-magnetic layer is in contact with the third magnetic layer and the first magnetic layer. The fifth non-magnetic layer is in contact with the second magnetic layer and the second magnetic pole.

5. The magnetic recording device according to claim 3, The first non-magnetic layer includes at least one selected from Cu, Au, Cr, Al, V and Ag. The second non-magnetic layer includes at least one selected from Cu, Au, Cr, Al, V and Ag. The third non-magnetic layer includes at least one selected from Cu, Au, Cr, Al, V and Ag. The fourth non-magnetic layer includes at least one selected from Ru, Ir, Ta, Rh, Pd, Pt and W, The fifth non-magnetic layer includes at least one selected from Ru, Ir, Ta, Rh, Pd, Pt, and W.

6. The magnetic recording device according to claim 4, The first non-magnetic layer includes at least one selected from Ru, Ir, Ta, Rh, Pd, Pt and W. The second non-magnetic layer includes at least one selected from Cu, Au, Cr, Al, V and Ag. The third non-magnetic layer includes at least one selected from Cu, Au, Cr, Al, V and Ag. The fourth non-magnetic layer includes at least one selected from Cu, Au, Cr, Al, V and Ag. The fifth non-magnetic layer includes at least one selected from Ru, Ir, Ta, Rh, Pd, Pt, and W.

7. The magnetic recording device according to claim 3, The first non-magnetic layer includes at least one selected from Ru, Ir, Ta, Rh, Pd, Pt and W. The second non-magnetic layer includes at least one selected from Cu, Au, Cr, Al, V and Ag. The third non-magnetic layer includes at least one selected from Ru, Ir, Ta, Rh, Pd, Pt and W. The fourth non-magnetic layer includes at least one selected from Cu, Au, Cr, Al, V and Ag. The fifth non-magnetic layer includes at least one selected from Ru, Ir, Ta, Rh, Pd, Pt, and W.

8. The magnetic recording device according to claim 1, The average anisotropic magnetic field Hk is greater than or equal to 17300 Oe and less than or equal to 21200 Oe, The dynamic coercive force Hc0 is greater than or equal to 7500 Oe and less than or equal to 11000 Oe.

9. The magnetic recording device according to claim 1, It also has component circuits, The element circuit can supply an element current having a direction from the first magnetic layer to the second magnetic layer to the magnetic element. When the element current is supplied to the magnetic element, an alternating magnetic field is generated from the magnetic element.

10. The magnetic recording device according to claim 1, It also has a recording circuit. The magnetic head further comprises a coil, The recording circuit is capable of supplying a recording current to the coil, Information corresponding to the recording current is recorded on the magnetic recording medium.

Images