Optical reflectors for use with a near-field transducer

Patent metadata

Field	Value
Publication number	US-9837112-B2
Application number	US-201514709705-A
Country	US
Kind code	B2
Filing date	May 12, 2015
Priority date	May 12, 2014
Publication date	Dec 5, 2017
Grant date	Dec 5, 2017

Abstract

An apparatus is includes a near field transducer positioned adjacent a media-facing surface and at the end of a waveguide having at least one core layer and a cladding layer. The apparatus also includes at least one optical reflector positioned adjacent opposing cross-track edges of the near field transducer and/or adjacent a down-track side of the near-field transducer.

First claim

What is claimed is:

1. An apparatus comprising:
a waveguide having at least one core layer and a cladding layer;
a near-field transducer positioned at an end of the waveguide and adjacent to a media-facing surface of a recording head;
first and second optical reflectors positioned adjacent opposing cross-track edges of the near-field transducer, at least part of the first and second optical reflectors located in the cladding layer, wherein the first and second optical reflectors are joined via a blocking region that is located downtrack from the near-field transducer; and
a solid-immersion mirror that focuses the light on to the near-field transducer, wherein the first and second optical reflectors block sidelobes generated by the solid-immersion mirror.

2. The apparatus of claim 1 , wherein the first and second optical reflectors are located adjacent a down-track side of the near-field transducer.

3. The apparatus of claim 1 , wherein the first and second optical reflectors block stray light generated proximate the near-field transducer.

4. The apparatus of claim 1 , wherein the first and second optical reflectors are thermally coupled to a heat sink positioned adjacent to the near-field transducer and the media-facing surface.

5. An apparatus comprising:
a dual core waveguide having first and second cores and a cladding layer, the first and second cores comprising layers that overlap each other in a downtrack direction;
a near-field transducer positioned at an end of the waveguide and adjacent to a media-facing surface of a recording head, the near-field transducer overlapping the layers of the first and second cores in the downtrack direction; and
first and second optical reflectors positioned adjacent opposing cross-track edges of the near-field transducer, at least part of the first and second optical reflectors located in the cladding layer, the first and second optical reflectors comprising a gold layer of a thickness that is greater than a skin depth of laser light in gold, the laser light being coupled into the waveguide to excite the near-field transducer.

6. The apparatus of claim 5 , further comprising a solid-immersion mirror that focuses the light on to the near-field transducer, wherein the first and second optical reflectors block sidelobes generated by a solid-immersion mirror.

7. The apparatus of claim 5 , wherein the first and second optical reflectors block sidelobes generated proximate the near-field transducer.

8. The apparatus of claim 5 , wherein the first and second optical reflectors block stray light generated proximate the near-field transducer.

9. The apparatus of claim 5 , wherein the optical reflectors are thermally coupled to a heat sink positioned adjacent to the near-field transducer and the media-facing surface.

10. The apparatus of claim 5 , wherein the first and second optical reflectors each comprise a surface facing away from and non-parallel to the media-facing surface, the surfaces reducing back-reflection of light to the waveguide.

11. The apparatus of claim 5 , wherein the first and second optical reflectors are joined via a blocking region that is located downtrack from the near-field transducer.

12. The apparatus of claim 5 , wherein the first and second optical reflectors are positioned at the media-facing surface.

13. The apparatus of claim 5 , wherein one of the first and second cores intersect with the first and second optical reflectors.

14. The apparatus of claim 5 , wherein the first and second cores are spaced apart from one another in the downtrack direction.

15. The apparatus of claim 5 , wherein the first and second cores are configured as channel waveguide cores.

16. The apparatus of claim 5 , further comprising a solid immersion mirror at the end of the waveguide, wherein the first and second cores are configured as planar waveguide cores.

17. An apparatus comprising:
a waveguide having at least one core layer and a cladding layer;
a near-field transducer positioned at an end of the waveguide and adjacent to a media-facing surface of a recording head;
blocking region positioned adjacent a down-track side of the near-field transducer, at least part of the blocking region located in the cladding layer, the blocking region blocking stray light generated proximate the near-field transducer; and
first and second optical reflectors positioned adjacent opposing cross-track edges of the near-field transducer, the first and second optical reflectors being joined via the blocking region downtrack from the near-field transducer.

18. The apparatus of claim 17 , wherein at least one of the optical reflectors is thermally coupled to a heat sink positioned adjacent to the near-field transducer and the media-facing surface.

19. The apparatus of claim 17 , wherein the waveguide comprises a channel waveguide.

Assignees

• Seagate Technology Llc

Inventors

• Yang Ruoxi
• Wessel James Gary
• Frakie Rachel
• Peng Chubing
• Scholz Werner
• Rea Chris
• Jandric Zoran
• Benakli Mourad
• Lee Tae-Woo

Classifications

• G11B5/314

  where the layers are extra layers normally not provided in the transducing structure, e.g. optical layers (G11B5/3196 takes precedence) · CPC title

• G11B5/3133

  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 title

• G02B2006/12121

  Laser · CPC title

• G11B7/24062

  Reflective layers · CPC title

• G02B6/02052

  comprising optical elements other than gratings, e.g. filters (comprising gratings G02B6/02057) · CPC title