Shaped plasmon generators for thermally-assisted magnetic recording

A TAMR head comprising:

• amagnetic write pole which, when energized, produces a magnetic field for writing on a magnetic recording medium;
• a stitched pole portion affixed to said write pole;
• a source of electromagnetic radiation;
• a waveguide for directing said electromagnetic radiation to an adjacent plasmon generator, wherein said electromagnetic radiation couples to a plasmon mode generated within said plasmon generator at a region of overlap between said waveguide and said plasmon generator;
• the plasmon generator for generating, propagating and condensing said plasmon mode as it propagates towards an ABS end of said plasmon generator and for transferring energy generated by said plasmon mode to a localized region of said magnetic recording medium, thereby heating said localized region and reducing its magnetic coercivity and anisotropy sufficiently for being written upon by said magnetic field;
• and wherein
• said plasmon generator is characterized by a non-uniform shape that includes a first portion of uniform horizontal cross-sectional area wherein said electromagnetic radiation from said adjacent waveguide is effective coupled to a plasmon mode, a second portion emerging from said portion of uniform horizontal cross-sectional area wherein the horizontal cross-sectional area of said second portion shrinks in area and change in shape in a direction towards said ABS end and within which said second portion said plasmon mode is condensed and focused as it propagates towards said ABS and a third potion of uniform cross-sectional shape emerging from said second portion wherein said third portion terminates at said ABS plane and effectively delivers said electromagnetic radiation from said surface plasmon mode to said magnetic recording medium.