Patent ID: 8325570

Claim:
A thermally-assisted magnetic recording head comprising: a medium facing surface that faces a magnetic recording medium; a magnetic pole that has an end face located in the medium facing surface and produces a write magnetic field for writing data on the magnetic recording medium; a waveguide including a core and a cladding, the core having a front end face that faces toward the medium facing surface and allowing light to propagate through; a plasmon generator having a near-field light generating part located in the medium facing surface, the plasmon generator being 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; and a protruding member disposed between the front end face of the core and the medium facing surface, wherein: the protruding member has a first end face located in the medium facing surface, and a second end face facing toward the front end face of the core and receiving light that has propagated through the core and passed through the front end face, the protruding member being formed of a metal that is different from both a material that forms the magnetic pole and a material that forms the plasmon generator; the second end face of the protruding member is opposed to at least part of the front end face of the core, the at least part having an area greater than 50% of an entire area of the front end face; and the protruding member is configured so that the light received at the second end face causes the protruding member to be heated and expanded to cause the first end face to get protruded toward the magnetic recording medium.