Reproducing head with spin-torque oscillator, and magnetic recording and reproducing apparatus

• US 8,755,153 B2
• Filed: 06/28/2012
• Issued: 06/17/2014
• Est. Priority Date: 09/12/2011
• Status: Active Grant

• Current Assignee: Kabushiki Kaisha Toshiba (Toshiba Corporation)
• Original Assignee: Kabushiki Kaisha Toshiba (Toshiba Corporation)
• Inventors: Kudo, Kiwamu, Nagasawa, Tazumi, Mizushima, Koichi, Sato, Rie, Yang, Tao, Suto, Hirofumi
• Primary Examiner(s): BLOUIN, MARK S
• Application Number:
  US13/535,785
• Publication Number:
  US 20130065086A1
• Time in Patent Office: 719 Days
• Field of Search: 360/321
• US Class Current: 360/321
• CPC Class Codes: G01R 33/098 comprising tunnel junctions, e.g. tunnel magnetoresistance sensors
• CPC Class Codes: G01R 33/1284 Spin resolved measurements; Influencing spins during measurements, e.g. in spintronics devices G01R33/093 takes precedence; semiconductor devices using spin polarized carriers H01L29/66984
• CPC Class Codes: G11B 2005/0002 Special dispositions or recording techniques
• CPC Class Codes: G11B 5/3903 using magnetic thin film layers or their effects, the films being part of integrated structures
• CPC Class Codes: G11B 5/3912 Arrangements in which the active read-out elements are transducing in association with active magnetic shields, e.g. magnetically coupled shields G11B5/3916 takes precedence
• CPC Class Codes: G11B 5/3929 Disposition of magnetic thin films not used for directly coupling magnetic flux from the track to the MR film or for shielding
• CPC Class Codes: H01F 10/325 the spacer being noble metal
• CPC Class Codes: H01F 10/3254 the spacer being semiconducting or insulating, e.g. for spin tunnel junction [STJ]
• CPC Class Codes: H01F 10/329 Spin-exchange coupled multilayers wherein the magnetisation of the free layer is switched by a spin-polarised current, e.g. spin torque effect
• CPC Class Codes: H01F 41/325 applying a noble metal capping on a spin-exchange-coupled multilayer, e.g. spin filter deposition
• CPC Class Codes: Y10T 428/1171 with defined laminate structural detail

Abstract

According to one embodiment, a reproducing head includes a spin-torque oscillator and a pair of shield parts. The spin-torque oscillator has a first surface facing a magnetic recording medium. The pair of shield parts each has a second surface facing the magnetic recording medium, the spin-torque oscillator being arranged between the shield parts. A distance between the second surface and the magnetic recording medium is shorter than a distance between the first surface and the magnetic recording medium.

Claims

1. A reproducing head with a spin-torque oscillator, the head comprising:

the spin-torque oscillator having a first surface facing a magnetic recording medium, the spin-torque oscillator used to detect a magnetic field from the magnetic recording medium; and

a pair of shield parts each having a second surface facing the magnetic recording medium, the spin-torque oscillator being arranged between the shield parts,

wherein a distance between the second surface and the magnetic recording medium is shorter than a distance between the first surface and the magnetic recording medium.

2. The head according to claim 1, further comprising an insulating layer formed in a portion enclosed by the pair of shield parts, the insulating layer having a third surface facing the magnetic recording medium,

wherein the third surface is flush with the second surface.

3. The head according to claim 1, wherein the spin-torque oscillator comprises a multilayered structure including an oscillation layer having rotatable magnetization.

4. The head according to claim 3, wherein the oscillation layer is arranged in a center between the pair of shield parts.

5. The head according to claim 3, further comprising a bias magnetic field source configured to apply a bias magnetic field to the oscillation layer.

6. The head according to claim 5, wherein the oscillation layer has a first axis defined in a longitudinal direction of a film surface of the oscillation layer, and a second axis defined in a lateral direction of the film surface, and is formed such that the second axis is parallel to a direction in which a medium magnetic field generated from the magnetic recording medium acts on the oscillation layer.

7. A magnetic recording and reproducing apparatus comprising the reproducing head with the spin-torque oscillator according to claim 1, and the magnetic recording medium.