Magnetic recording apparatus having magnetic flux control part and magnetic recording head having magnetic flux control part

• US 10,236,021 B2
• Filed: 08/28/2017
• Issued: 03/19/2019
• Est. Priority Date: 03/17/2017
• Status: Active Grant

• Current Assignee: Kabushiki Kaisha Toshiba (Toshiba Corporation)
• Original Assignee: Kabushiki Kaisha Toshiba (Toshiba Corporation)
• Inventors: Narita, Naoyuki, Takagishi, Masayuki, Yamada, Kenichiro, Maeda, Tomoyuki, Takeo, Akihiko
• Primary Examiner(s): Evans, Jefferson
• Application Number:
  US15/687,570
• Publication Number:
  US 20180268848A1
• Time in Patent Office: 568 Days
• Field of Search: 36011902, 36011903, 3601253
• CPC Class Codes: G11B 2005/0024 Microwave assisted recording
• CPC Class Codes: G11B 5/1278 specially adapted for magnetisations perpendicular to the surface of the record carrier
• CPC Class Codes: G11B 5/23 Gap features G11B5/1871, G11B5/1875, G11B5/265, G11B5/29, G11B5/488 and subgroups, G11B5/4907 and subgroups, G11B5/4969 and subgroups take precedence
• CPC Class Codes: G11B 5/3133 including layers not usually being a part of the electromagnetic transducer structure and providing additional features, e.g. for improving heat radiation, reduction of power dissipation, adaptations for measurement or indication of gap depth or other properties of the structure G11B5/3106 takes precedence
• CPC Class Codes: G11B 5/3153 including at least one magnetic thin film coupled by interfacing to the basic magnetic thin film structure
• CPC Class Codes: G11B 5/33 Structure or manufacture of flux-sensitive heads, i.e. for reproduction only; Combination of such heads with means for recording or erasing onlySingle head using magnetic domains for scanning G11B5/4946; multiple head for scanning G11B5/4907 and subgroups ; general details therefor G11B5/133 - G11B5/255
• CPC Class Codes: G11B 5/3983 with current confined paths in the spacer layer

Abstract

A magnetic recording apparatus includes a magnetic recording medium; a magnetic recording head including a first magnetic pole part, a second magnetic pole part, and a magnetic flux control part provided between the first magnetic pole part and the second magnetic pole part, wherein the magnetic flux control part includes a first layer provided between the first magnetic pole part and the second magnetic pole part, a second layer provided between the first magnetic pole part and the first layer, and a third layer provided between the second magnetic pole part and the first layer; an electrode for applying a current to the magnetic flux control part; and an electric circuit for energizing the current to the electrode, wherein an oscillation frequency of magnetization of the magnetic layer is greater than a ferromagnetic resonance frequency of the magnetic recording medium.

Claims

1. A magnetic recording apparatus comprising:

a magnetic recording medium;

a magnetic recording head, which is capable of recording data on the magnetic recording medium, the magnetic recording head including;

a first magnetic pole part;

a second magnetic pole part; and

a magnetic flux control part provided between the first magnetic pole part and the second magnetic pole part,

wherein the magnetic flux control part comprises;

a first layer being provided as a magnetic flux control layer between the first magnetic pole part and the second magnetic pole part and including at least one element selected from the group consisting of Fe, Co, and Ni;

a second layer provided between the first magnetic pole part and the first layer and including at least one element selected from the group consisting of Cu, Ag, and Au; and

a third layer provided between the second magnetic pole part and the first layer and including at least one element selected from the group consisting of Cu, Ag, and Au;

an electrode for applying a current to the magnetic flux control part; and

an electric circuit for energizing the current to the electrode and causing a gap magnetic field between the first magnetic pole part and the second magnetic pole part,

wherein an oscillation frequency of magnetization of the first layer for recording is greater than a ferromagnetic resonance frequency of the magnetic recording medium while the first layer has a component antiparallel to the gap magnetic field after a magnetization direction of the first layer is inverted.

2. The magnetic recording apparatus according to claim 1, wherein an anisotropic magnetic field of the first layer is positive.

3. The magnetic recording apparatus according to claim 1 or 2, wherein the current energized to the first layer is a direct current.

4. The magnetic recording apparatus according to claim 1,

wherein a film thickness of the first layer is thicker than a film thickness of the second layer and the third layer.

5. The magnetic recording apparatus according to claim 1, wherein a value of the anisotropic magnetic field of the first layer is in a range surrounded by a first value (Hk1) and a second value (Hk2) shown by the following Equation:

6. A magnetic recording head, which is capable of recording data on the magnetic recording medium, the magnetic recording head comprising:

a first magnetic pole part;

a second magnetic pole part, a gap magnetic field being generated between the first magnetic pole part and the second magnetic pole part; and

a magnetic flux control part provided between the first magnetic pole part and the second magnetic pole part,

wherein the magnetic flux control part comprises;

a first layer being provided as a magnetic flux control layer between the first magnetic pole part and the second magnetic pole part and including at least one element selected from the group consisting of Fe, Co, and Ni;

a second layer provided between the first magnetic pole part and the first layer and including at least one element selected from Pt, W, Ta, Ru, and Pd; and

a third layer provided between the second magnetic pole part and the first layer and including at least one element selected from the group consisting of Cu, Ag, and Au, and

wherein an oscillation frequency of magnetization of the first layer for recording is greater than a ferromagnetic resonance frequency of the magnetic recording medium while the first layer has a component antiparallel to the gap magnetic field after a magnetization direction of the first layer is inverted.

7. The magnetic recording head according to claim 6, wherein the second layer further comprises at least one element selected from the group consisting of Cu, Ag, and Au.

8. The magnetic recording head according to claim 6 or 7, wherein the second layer is constituted by a laminate having a portion comprising at least one element selected from Pt, W, Ta, Ru, and Pd and a portion comprising at least one element selected from the group consisting of Cu, Ag, and Au.

9. The magnetic recording head according to claim 6, wherein the second layer is a laminate having a portion comprising at least one element selected from Pt, W, Ta, Ru, and Pd in the vicinity of a surface contacting the first magnetic pole part.

10. The magnetic recording head according to claim 6, wherein the second layer is a laminate having a portion comprising at least one element selected from Pt, W, Ta, Ru, and Pd in the vicinity of a surface contacting the first layer.

11. The magnetic recording head according to claim 6, wherein the second layer is a laminate having a portion comprising at least one element selected from Pt, W, Ta, Ru, and Pd in the vicinity of a surface contacting the first magnetic pole part and a surface contacting the first layer.

12. A magnetic recording apparatus comprising:

the magnetic recording head according to claim 6;

a magnetic recording medium on which information is recorded by the magnetic recording head; and

a first electric circuit, which is capable of supplying a current to the magnetic flux control part of the magnetic recording head.

13. The magnetic recording apparatus according to claim 12, further comprising a second electric circuit,

wherein the magnetic recording head further comprises a coil, and

the second electric circuit is capable of supplying a current corresponding to the information to the coil.

14. A magnetic recording head, which is capable of recording data on the magnetic recording medium, the magnetic recording head comprising:

a first magnetic pole part;

a second magnetic pole part; and

a magnetic flux control part provided between the first magnetic pole part and the second magnetic pole part,

wherein the magnetic flux control part comprises;

a first layer being provided as a magnetic flux control layer between the first magnetic pole part and the second magnetic pole part and including at least one element selected from the group consisting of Fe, Co, and Ni;

a second layer provided between the first magnetic pole part and the first layer and including at least one element selected from the group consisting of Cu, Ag, and Au; and

a third layer provided between the second magnetic pole part and the first layer and including at least one element selected from Pt, W, Ta, Ru, and Pd, and

wherein a film thickness of the first layer is thicker than a film thickness of the second layer and the third layer.

15. The magnetic recording head according to claim 14, wherein the third layer further comprises at least one element selected from the group consisting of Cu, Ag, and Au.

16. The magnetic recording head according to claim 14 or 15, wherein the third layer is constituted by a laminate having a portion comprising at least one element selected from Pt, W, Ta, Ru, and Pd and a portion comprising at least one element selected from the group consisting of Cu, Ag, and Au.

17. The magnetic recording head according to claim 14, wherein the third layer is a laminate having a portion comprising at least one element selected from Pt, W, Ta, Ru, and Pd in the vicinity of a surface contacting the first layer.

18. The magnetic recording head according to claim 14, wherein the third layer is a laminate having a portion comprising at least one element selected from Pt, W, Ta, Ru, and Pd in the vicinity of a surface contacting the second magnetic pole part.

19. The magnetic recording head according to claim 14, wherein the third layer is a laminate having a portion comprising at least one element selected from Pt, W, Ta, Ru, and Pd in the vicinity of a surface contacting the second magnetic pole part and a surface contacting the first layer.

20. The magnetic recording head according to claim 14, wherein an oscillation frequency of the first layer is greater than 35 GHz in a recording operation.