Systems and methods for increasing media absorption efficiency using interferometric waveguides
View Patent ↗Systems and methods for increasing media absorption efficiency using interferometric waveguides in information storage devices are described. One such system for an interferometric waveguide assembly includes a light source, a first waveguide arm and a second waveguide arm, a splitter configured to receive light from the light source and to split the light into the first waveguide arm and the second waveguide arm, and a near field transducer (NFT) configured to receive the light from the first waveguide arm and the second waveguide arm, where the first waveguide arm and the second waveguide arm converge to form a preselected angle at a junction about opposite the splitter, and where the first waveguide arm and the second waveguide arm are configured to induce a preselected phase difference in the light arriving at the NFT.
1. An interferometric waveguide assembly comprising:
a light source;
a first waveguide arm and a second waveguide arm;
a splitter configured to receive light from the light source and to split the light into the first waveguide arm and the second waveguide arm; and
a near field transducer (NFT) configured to receive the light from the first waveguide arm and the second waveguide arm,
wherein the first waveguide arm and the second waveguide arm converge to form a preselected angle at a junction opposite the splitter in a light propagating direction, and
wherein the first waveguide arm and the second waveguide arm are configured to induce a preselected phase difference in the light arriving at the NFT.
2. The waveguide assembly of claim 1 , wherein the NFT is proximate the junction.
3. The waveguide assembly of claim 1 , wherein the preselected phase difference is about 180 degrees multiplied by (2n+1), where n is an integer.
4. The waveguide assembly of claim 1 , wherein the preselected angle ranges from about 80 degrees to about 140 degrees, inclusive.
5. The waveguide assembly of claim 1 , wherein the first waveguide arm and the second waveguide arm comprise a different characteristic to induce the preselected phase difference, wherein the characteristic is selected from the group consisting of a width, a length, a material, a side wall angle, and combinations thereof.
6. The waveguide assembly of claim 1 , further comprising a phase retarder positioned proximate the first waveguide arm, the phase retarder comprising a preselected material and configured to induce the preselected phase difference.
7. The waveguide assembly of claim 1 , further comprising a heat source proximate the first waveguide arm, the heat source configured to induce the preselected phase difference.
8. The waveguide assembly of claim 1 , further comprising an electrode positioned proximate the first waveguide arm, the electrode configured to apply an electric field to the first waveguide arm and thereby induce the preselected phase difference.
9. The waveguide assembly of claim 1 , wherein the splitter is configured to split the light about equally between the first waveguide arm and the second waveguide arm.
10. The waveguide assembly of claim 1 , wherein the splitter comprises a preselected splitter selected from the group consisting of a Y-splitter, a multi-mode interference splitter, a directional coupler splitter, and combinations thereof.
11. The waveguide assembly of claim 1 , wherein each of the first waveguide arm and the second waveguide arm comprise an S-bend extending to a joining arm, and wherein each of the joining arms converges at the junction proximate the NFT.
12. The waveguide assembly of claim 1 , wherein the light source comprises a laser.
13. The waveguide assembly of claim 1 :
wherein the waveguide assembly is positioned proximate a magnetic media disk, and
wherein the NFT is configured to convert the received light into electromagnetic energy and direct the electromagnetic energy on a preselected area of the media disk.
14. A method for forming an interferometric waveguide assembly, the method comprising:
forming a reader;
forming a return pole on the reader;
forming a cladding layer on the return pole;
forming a core layer on the cladding layer;
forming the interferometric waveguide assembly within the core layer, wherein the interferometric waveguide assembly comprises:
a first waveguide arm and a second waveguide arm; and
a splitter configured to receive light from a light source and to split the light into the first waveguide arm and the second waveguide arm,
wherein the first waveguide arm and the second waveguide arm converge to form a preselected angle at a junction opposite the splitter in a light propagating direction, and
wherein the first waveguide arm and the second waveguide arm are configured to induce a preselected phase difference in the light arriving at a near field transducer (NFT); and
forming a write pole on the waveguide assembly.
15. The method of claim 14 , further comprising forming the NFT on the interferometric waveguide assembly.
16. The method of claim 14 , wherein the forming the interferometric waveguide assembly on the core layer comprises:
forming the NFT on the core layer; and
forming the interferometric waveguide assembly on the NFT.
17. The method of claim 14 :
wherein the forming the reader comprises forming a write shield on the reader;
wherein the forming the return pole on the reader comprises forming the return pole on the write shield; and
wherein the forming the write pole on the waveguide assembly comprises:
forming the NFT;
forming a heat sink on the NFT;
depositing the write pole on the heat sink;
shaping the write pole; and
depositing a top cladding layer on the shaped write pole.
18. The method of claim 14 , wherein the NFT is proximate the junction.
19. The method of claim 14 , wherein the preselected phase difference is about 180 degrees multiplied by (2n+1), where n is an integer.
20. The method of claim 14 , wherein the preselected angle ranges from about 80 degrees to about 140 degrees, inclusive.
21. The method of claim 14 , wherein the first waveguide arm and the second waveguide arm comprise a different characteristic to induce the preselected phase difference, wherein the characteristic is selected from the group consisting of a width, a length, a material, a side wall angle, and combinations thereof.
22. The method of claim 14 , further comprising a phase retarder positioned proximate the first waveguide arm, the phase retarder comprising a preselected material and configured to induce the preselected phase difference.
23. The method of claim 14 , further comprising a heat source proximate the first waveguide arm, the heat source to induce the preselected phase difference.
24. The method of claim 14 , further comprising an electrode positioned proximate the first waveguide arm, the electrode configured to apply an electric field to the first waveguide arm and thereby induce the preselected phase difference.
25. The method of claim 14 , wherein the splitter is configured to split the light about equally between the first waveguide arm and the second waveguide arm.
26. The method of claim 14 , wherein the splitter comprises a preselected splitter selected from the group consisting of a Y-splitter, a multi-mode interference splitter, a directional coupler splitter, and combinations thereof.
27. The method of claim 14 , wherein each of the first waveguide arm and the second waveguide arm comprise an S-bend extending to a joining arm, and wherein each of the joining arms converges at the junction proximate the NFT.
28. The method of claim 14 , wherein the light source comprises a laser.
29. The method of claim 14 :
wherein the waveguide assembly is positioned proximate a magnetic media disk, and
wherein the NFT is configured to convert the received light into electromagnetic energy and direct the electromagnetic energy on a preselected area of the media disk.