Patent ID: 8619517

Claim:
A thermally-assisted magnetic recording head comprising: a medium facing surface that faces a recording medium; a main pole that has an end face located in the medium facing surface and produces a write magnetic field for writing data on the recording medium; a waveguide including a core through which light propagates, and a cladding that surrounds the core; and a plasmon generator having a near-field light generating part located in the medium facing surface, wherein: the core has an evanescent light generating surface that generates evanescent light based on the light propagating through the core; the plasmon generator has a plasmon exciting part that is opposed to the evanescent light generating surface with a predetermined distance therebetween; the cladding includes an interposer interposed between the evanescent light generating surface and the plasmon exciting part; assuming a virtual straight line that passes internally through the core and that is parallel to a direction of travel of the light propagating through the core, at least part of the evanescent light generating surface and at least part of the plasmon exciting part are both inclined relative to the virtual straight line such that a distance from the virtual straight line decreases with increasing proximity to the medium facing surface; and the plasmon generator is configured so that a surface plasmon is excited on the plasmon exciting part through coupling with the evanescent light generated from the evanescent light generating surface, the surface plasmon propagates to the near-field light generating part, and the near-field light generating part generates near-field light based on the surface plasmon.