Spin torque oscillator and magnetic recording apparatus

• US 8,467,149 B2
• Filed: 08/25/2011
• Issued: 06/18/2013
• Est. Priority Date: 11/26/2010
• Status: Active Grant

• Current Assignee: Kabushiki Kaisha Toshiba (Toshiba Corporation)
• Original Assignee: Kabushiki Kaisha Toshiba (Toshiba Corporation)
• Inventors: Takeo, Akihiko, Koui, Katsuhiko, Iwasaki, Hitoshi, Fujita, Norihito, Kitazaki, Mariko
• Primary Examiner(s): BLOUIN, MARK S
• Application Number:
  US13/218,297
• Publication Number:
  US 20120134048A1
• Time in Patent Office: 663 Days
• Field of Search: 360/125.3
• US Class Current: 360/125.3
• CPC Class Codes: G11B 2005/0024 Microwave assisted recording
• CPC Class Codes: G11B 5/314 where the layers are extra layers normally not provided in the transducing structure, e.g. optical layers G11B5/3196 takes precedence
• CPC Class Codes: G11B 5/3146 magnetic layers
• CPC Class Codes: Y10T 428/1171 with defined laminate structural detail

Abstract

According to one embodiment, a spin torque oscillator includes a field generation layer, a spin injection layer including a first layer and a second layer, and an interlayer interposed between the field generation layer and the spin injection layer, wherein the first layer is interposed between the second layer and the interlayer and includes a (001)-oriented Heuslar magnetic alloy or a (001)-oriented magnetic material having a body-centered cubic lattice structure.

Claims

1. A spin torque oscillator comprising:

a field generation layer in which spins make a precession movement;

a spin injection layer, in which spins are fixed in a thickness direction, comprising a first layer and a second layer; and

an interlayer between the field generation layer and the spin injection layer,

wherein the first layer is between the second layer and the interlayer and comprises a (001)-oriented magnetic material having a body-centered cubic lattice structure or a (001)-oriented Heuslar magnetic alloy.

2. The spin torque oscillator of claim 1, wherein the second layer comprises a (001)-oriented magnetic material with perpendicular magnetic anisotropy.

3. The spin torque oscillator of claim 2, wherein the (001)-oriented magnetic material with perpendicular magnetic anisotropy is a Fe—

Pt alloy, a Fe—

Pd alloy, a Co—

Pt alloy, or a Co—

Pd alloy.

4. The spin torque oscillator of claim 2, further comprising a buffer layer, wherein the second layer is between the buffer layer and the first layer, and the buffer layer comprises (001)-oriented Cr or a (001)-oriented Al—

Ni alloy.

5. The spin torque oscillator of claim 4, further comprising an underlayer, wherein the buffer layer is between the underlayer and the second layer, and the underlayer has an amorphous structure and comprises Ta or an alloy comprising Ni and one or more of Ta, Nb, and Zr.

6. The spin torque oscillator of claim 1, wherein the first layer comprises the (001)-oriented Heuslar magnetic alloy and the alloy is Co2MnSi, Co2MnAl, Co2MnGe, or CoCrFeAl.

7. The spin torque oscillator of claim 1, wherein the first layer comprises the (001)-oriented magnetic material having a body-centered cubic lattice structure, and the material is an alloy comprising at least one metal selected from the group consisting of Fe, Co, and Ni.

8. The spin torque oscillator of claim 1, wherein the field generation layer comprises a magnetic material.

9. The spin torque oscillator of claim 8, wherein the magnetic material is an alloy comprising at least one metal selected from the group consisting of Fe, Co, and Ni.

10. The spin torque oscillator of claim 1, wherein the interlayer comprises a nonmagnetic material.

11. The spin torque oscillator of claim 10, wherein the nonmagnetic material is Cu, Au, or Ag.

12. A magnetic recording apparatus comprising:

a magnetic recording medium; and

a magnetic recording head comprising the spin torque oscillator of claim 1.