Patent ID: 8498183
Filing Date: 2013-07-30
Classification: G11B

Abstract:
1. A thermally-assisted magnetic recording head comprising: a medium facing surface that faces a recording medium; a coil that produces a magnetic field corresponding to data to be written on the recording medium; a main pole having a first end face located in the medium facing surface, the main pole allowing a magnetic flux that corresponds to the magnetic field produced by the coil to pass, and producing a write magnetic field for writing the data on the recording medium; a return path section made of a magnetic material and having a second end face located in the medium facing surface, the return path section being connected to the main pole so that a space through which part of the coil passes is defined by the main pole and the return path section; a waveguide including a core through which light propagates, and a cladding provided around the core; and a plasmon generator having a near-field light generating part located in the medium facing surface, wherein: the first end face and the second end face are located at positions that are different from each other in a direction of travel of the recording medium; the near-field light generating part is located between the first end face and the second end face; the plasmon generator is configured so that a surface plasmon is excited on the plasmon generator based on the light propagating through the core, and the near-field light generating part generates near-field light based on the surface plasmon; the return path section includes: first and second columnar portions that are located on opposite sides of the core in a track width direction and are each spaced from the core; a coupling portion coupling the first and second columnar portions to each other; and a third columnar portion connected to the coupling portion; the third columnar portion is located such that the coupling portion is interposed between the third columnar portion and the core; the third columnar portion is smaller than the coupling portion in width in the track width direction; and the coil includes a first winding portion wound around the third columnar portion.