Near-field light generating element comprising surface plasmon antenna and waveguide with groove

A thermally-assisted magnetic recording head comprising:

• a magnetic pole for generating write field from its end on an opposed-to-medium surface side;
• a waveguide through which a light for exciting surface plasmon propagates;
• and
• a plasmon antenna comprising:
• a near-field light generating end for emitting near-field light, reaching the opposed-to-medium surface;
• and a propagation surface or a propagation edge for causing surface plasmon excited by the light to propagate thereon, extending to said near-field light generating end,
• a groove being formed in a side surface of said waveguide, and at least a portion of said propagation surface or said propagation edge being embedded in said groove or being located directly above said groove, said at least a portion being opposed to a wall surface or a bottom surface of said groove with a predetermined distance, so as for the light propagating through said waveguide to be coupled with said plasmon antenna in a surface plasmon mode.

A magnetic recording apparatus comprising:

• at least one head gimbal assembly comprising a thermally-assisted magnetic recording head and a suspension supporting said thermally-assisted magnetic recording head;
• at least one magnetic recording medium;
• and
• a recording circuit for controlling write operations which said thermally-assisted magnetic recording head performs to said at least one magnetic recording medium,
• said thermally-assisted magnetic recording head comprising:
• a magnetic pole for generating write field from its end on an opposed-to-medium surface side;
• a waveguide through which a light for exciting surface plasmon propagates;
• and
• a plasmon antenna comprising:
• a near-field light generating end for emitting near-field light, reaching the opposed-to-medium surface;
• and a propagation surface or a propagation edge for causing surface plasmon excited by the light to propagate thereon, extending to said near-field light generating end,
• a groove being formed in a side surface of said waveguide, and at least a portion of said propagation surface or said propagation edge being embedded in said groove or being located directly above said groove, said at least a portion being opposed to a wall surface or a bottom surface of said groove with a predetermined distance, so as for the light propagating through said waveguide to be coupled with said plasmon antenna in a surface plasmon mode, and
• said recording circuit further comprising a light-emission control circuit for controlling operations of a light source that generates the light for exciting surface plasmon.