Magnetic flux barrier

• US 9,171,555 B2
• Filed: 02/06/2015
• Issued: 10/27/2015
• Est. Priority Date: 09/10/2010
• Status: Active Grant

• Current Assignee: Seagate Technology LLC (Seagate Technology Holdings Plc)
• Original Assignee: Seagate Technology LLC (Seagate Technology Holdings Plc)
• Inventors: Meloche, Eric, Lu, Bin, Jia, Lixin, Xue, Jianhua, Westwood, John David, Gubbins, Mark Anthony, Cazacu, Alexandru
• Primary Examiner(s): Young, Wayne
• Assistant Examiner(s): Garcia, Carlos E
• Application Number:
  US14/615,940
• Publication Number:
  US 20150154985A1
• Time in Patent Office: 263 Days
• Field of Search: 360/235.4
• US Class Current: 1/1
• CPC Class Codes: G11B 5/11 Shielding of head against electric or magnetic fields
• CPC Class Codes: G11B 5/1278 specially adapted for magnetisations perpendicular to the surface of the record carrier
• CPC Class Codes: G11B 5/3116 Shaping of layers, poles or gaps for improving the form of the electrical signal transduced, e.g. for shielding, contour effect, equalizing, side flux fringing, cross talk reduction between heads or between heads and information tracks G11B5/3113, G11B5/245 take precedence
• CPC Class Codes: G11B 5/315 Shield layers on both sides of the main pole, e.g. in perpendicular magnetic heads

Abstract

Data storage systems having barriers that may reduce erasure flux and increase write-ability are provided. Data storage systems include a writing element. The writing element has a write pole with a flare region. A magnetic flux barrier is located along the write pole flare region. The magnetic flux barrier is illustratively made from an in-plane magnetically anisotropic material that has an easy plane of magnetization. In another embodiment, a data storage system includes a writing element having an air bearing surface and a shield at the air bearing surface. The shield has a magnetic permeability of approximately zero. The shield illustratively includes alternating layers of positive and negative permeabilities. The shield optionally includes a plurality of shields that may include top, bottom, and side shields.

Claims

1. A data storage system writing element comprising:

an air bearing surface; and

a shield at the air bearing surface, the shield having multiple layers and a magnetic permeability of approximately zero, wherein the multiple layers include at least one layer having a positive magnetic permeability and at least one layer having a negative magnetic permeability.

2. The writing element of claim 1, further comprising:

an electrical signal filter.

3. The writing element of claim 1, wherein the multiple layers include alternating layers of positive and negative magnetic permeabilities.

4. The writing element of claim 3, wherein each of the multiple layers has a thickness that is between five and fifty nanometers.

5. The writing element of claim 1, wherein the shield comprises a plurality of shields.

6. The writing element of claim 5, wherein the plurality of shields includes a top shield and a bottom shield.

7. The writing element of claim 5, wherein the plurality of shields includes side shields.

8. A recording head comprising:

a write pole having a flare region;

an air bearing surface;

an in-plane magnetically anisotropic layer along the flare region; and

shields along the air bearing surface, the shields having a magnetic permeability of approximately zero,

wherein at least one of the shields comprises multiple layers, and

wherein the multiple layers include at least one layer having a positive magnetic permeability and at least one layer having a negative magnetic permeability.

9. The recording head of claim 8, further comprising:

a capacitor in electrical series with the write pole.

10. The recording head of claim 8, wherein the shields include top and bottom shields.

11. The recording head of claim 8, wherein the shields include side shields.

12. The recording head of claim 8, wherein all of the shields comprise multiple layers.

13. The recording head of claim 12, wherein the shields include alternating layers of positive and negative permeabilities.

14. A data storage system writing element comprising:

a write pole having a flare region and a tip region;

an air bearing surface;

shields along the air bearing surface;

a magnetic flux barrier along the write pole flare region; and

the shields having a magnetic permeability of approximately zero,

wherein at least one of the shields comprises multiple layers, and

wherein the multiple layers include at least one layer having a positive magnetic permeability and at least one layer having a negative magnetic permeability.

15. The writing element of claim 14, wherein the writing element further comprises a dielectric layer, the dielectric layer being separated from the flare region by the magnetic flux barrier, and the dielectric layer being in direct contact with at least a portion of the tip region.

16. The writing element of claim 14, wherein the magnetic flux barrier extends beyond the write pole flare region and covers at least a portion of the tip region.

17. The recording head of claim 14, wherein the shields include top and bottom shields.

18. The recording head of claim 14, wherein the shields include side shields.

19. The recording head of claim 14, wherein all of the shields comprise multiple layers.

20. The recording head of claim 19, wherein the shields include alternating layers of positive and negative permeabilities.