# US 10,770,098 B1 · Heat-assisted magnetic recording head with near-field transducer having first and second surface-plasmonic plates > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 10,770,098 B1 - Document ID: US10770098B1 - Status: Granted - Kind: B1 - Application number: 16/591,999 - Filed: 2019-10-03 - Granted: 2020-09-08 - Earliest claimed: 2018-10-08 - Assignees: Seagate Technology LLC - Applicants: Seagate Technology LLC - Inventors: Chubing Peng - Web page: https://patentgrep.com/patent/US10770098B1 ## CPC - G11B 5/314: {where the layers are extra layers normally not provided in the transducing structure, e.g. optical layers (G11B5/3196 takes precedence)} - 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)} - G11B 5/3133: {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)} - G11B 5/4866: {the arm comprising an optical waveguide, e.g. for thermally-assisted recording} - G11B 5/6088: {Optical waveguide in or on flying head} - G11B 7/1387: using the near-field effect - G11B 5/3109: {Details (G11B5/3103 takes precedence)} - G11B 2005/0021: {Thermally assisted recording using an auxiliary energy source for heating the recording layer locally to assist the magnetization reversal} - G11B: INFORMATION STORAGE BASED ON RELATIVE MOVEMENT BETWEEN RECORD CARRIER AND TRANSDUCER (recording measured values in a way that does not require playback through a transducer G01D9/00; recording or playback apparatus using mechanically marked tape, e.g. punched paper tape, or using unit records, e.g. punched or magnetically marked cards G06K; transferring data from one type of record carrier to another G06K1/18; circuits for coupling output of reproducer to radio receiver H04B1/20; gramophone pick-ups or like acoustic electromechanical transducers or circuits therefor H04R) ## Abstract A write head includes a first surface-plasmonic plate proximate a magnetic pole and recessed from a media-facing surface of the write head. A bottom surface of the first surface-plasmonic plate faces away from the magnetic pole and towards a waveguide core. The first surface-plasmonic plate is formed of a first material having lower-loss in plasmonic coupling than a second material, the second material being more mechanically robust than the first material. A second surface-plasmonic plate is formed of the second material and located on the bottom surface of the first surface-plasmonic plate. A lower edge of the second surface-plasmonic plate extends closer to the media-facing surface than the first surface-plasmonic plate. An upper edge of the second surface-plasmonic plate is slanted in a downtrack direction. ## Claims ### Claim 1 A write head comprising: a waveguide core; a magnetic pole; a first surface-plasmonic plate proximate the magnetic pole and recessed from a media-facing surface of the write head, a bottom surface of the first surface-plasmonic plate facing away from the magnetic pole and towards the waveguide core, the first surface-plasmonic plate formed of a first material having lower-loss in plasmonic coupling than a second material, the second material being more mechanically robust than the first material; and a second surface-plasmonic plate formed of the second material and located on the bottom surface of the first surface-plasmonic plate, a lower edge of the second surface-plasmonic plate extending closer to the media-facing surface than the first surface-plasmonic plate, the second surface-plasmonic plate comprising a peg that extends from the lower edge to the media-facing surface, an upper edge of the second surface-plasmonic plate slanted in a downtrack direction. ### Claim 2 (depends on 1) The write head of claim 1, wherein overlapping portions of the first and second surface-plasmonic plates have a same, in-plane, crosstrack edge shape. ### Claim 3 (depends on 2) The write head of claim 2, wherein the crosstrack edge shape comprises a parabolic shape. ### Claim 4 (depends on 1) The write head of claim 1, wherein the first material comprises at least one of Au, Au-Alloy, Ag, and Cu. ### Claim 5 (depends on 1) The write head of claim 1, wherein the second material comprises at least one of Rh, Ir, nitrides (TiN, TaN), Pt, and Pd. ### Claim 6 (depends on 1) The write head of claim 1, further comprising first and second optical side shields on first and second crosstrack sides of the first and second surface-plasmonic plates, the first and second optical side shields elongated and slanted relative to the media-facing surface in a crosstrack direction. ### Claim 7 (depends on 1) The write head of claim 1, wherein the waveguide core narrows in a crosstrack direction as it approaches the media-facing surface. ### Claim 8 (depends on 1) The write head of claim 1, wherein a terminating edge of the waveguide core has a slanted surface that faces away from the write pole, the write head further comprising a funnel coupler spaced away from the slanted surface and having a reflective surface parallel to the slanted surface. ### Claim 9 (depends on 1) The write head of claim 1, wherein the upper edge of the second surface-plasmonic plate is slanted between 20 and 70 degrees relative to a bottom surface of the second surface-plasmonic plate. ### Claim 10 A write head comprising: a waveguide core; a magnetic pole; and a near-field transducer comprising stacked and partially overlapping first and second plasmonic plates between the waveguide core and the magnetic pole, the first surface-plasmonic plate facing the magnetic pole and the second plasmonic plate facing the waveguide core, the first plasmonic plate recessed further from a media-facing surface of the write head than a lower edge of the second plasmonic plate, the first surface-plasmonic plate formed of a first material having lower-loss in plasmonic coupling than a second material used to form the second surface plasmonic plate, the second surface-plasmonic plate comprising a peg that extends from the lower edge, an upper edge of the second surface-plasmonic plate slanted at an angle relative to the waveguide core. ### Claim 11 (depends on 10) The write head of claim 10, wherein the second material is more mechanically robust than the first material. ### Claim 12 (depends on 10) The write head of claim 10, wherein overlapping portions of the first and second surface-plasmonic plates have a same, in-plane, crosstrack edge shape. ### Claim 13 (depends on 12) The write head of claim 12, wherein the crosstrack edge shape comprises a circular shape. ### Claim 14 (depends on 10) The write head of claim 10, further comprising first and second optical side shields on first and second crosstrack sides of the first and second surface-plasmonic plates, the first and second optical side shields elongated and slanted relative to the media-facing surface in a crosstrack direction. ### Claim 15 (depends on 10) The write head of claim 10, wherein the waveguide core narrows in a crosstrack direction as it approaches the media-facing surface. ### Claim 16 (depends on 10) The write head of claim 10, wherein a terminating edge of the waveguide core has a slanted surface that faces away from the write pole, the write head further comprising a funnel coupler spaced away from the slanted surface and having a reflective surface parallel to the slanted surface. ### Claim 17 (depends on 10) The write head of claim 10, wherein the upper edge of the second surface-plasmonic plate is slanted between 20 and 70 degrees relative to a bottom surface of the second surface-plasmonic plate. ### Claim 18 A method comprising: coupling light into a waveguide core that delivers the light proximate to a media-facing surface of a write head; coupling the light from the waveguide to a first surface-plasmonic plate proximate a magnetic pole and recessed from the media-facing surface of the write head, the light generating surface-plasmon polaritons on a bottom surface of the first surface-plasmonic plate, the bottom surface facing away from the magnetic pole and towards the waveguide core, the first surface-plasmonic plate being formed of a first material having lower-loss in plasmonic coupling than a second material, the second material being more mechanically robust than the first material; and couple the surface-plasmon polaritons from the bottom surface of the first surface-plasmonic plate to a second surface-plasmonic plate formed of the second material and located on the bottom surface of the first surface-plasmonic plate, a lower edge of the second surface-plasmonic plate extending closer to the media-facing surface than the first surface-plasmonic plate and having a peg that extends from the lower edge and directs the surface-plasmon polaritons out of the media-facing surface towards a recording medium. ### Claim 19 (depends on 18) The method of claim 18, wherein the light is coupled to the waveguide in a fundamental transverse magnetic mode. ### Claim 20 (depends on 18) The method of claim 18, further comprising applying a magnetic field to a hotspot on the recording medium formed by the surface-plasmon polaritons, the magnetic field recording data to the hotspot.