Planar waveguide for heat assisted magnetic recording

A disc drive comprising:

• means for rotating a storage medium;
• and
• means for positioning a recording head adjacent to a surface of the storage medium;
• wherein the recording head comprises a magnetic write pole and a planar waveguide positioned adjacent to the magnetic write pole, the planar waveguide including a first metal layer, a second metal layer, a first optical layer positioned between the first and second metal layers, and means for coupling an electromagnetic wave to the first optical layer at a resonant incident angle.

A disc drive comprising:

• means for rotating a storage medium;
• and
• means for positioning a recording head adjacent to a surface of the storage medium;
• wherein the recording head comprises a magnetic write pole and a planar waveguide positioned adjacent to the magnetic write pole, the planar waveguide including a first metal layer, a second metal layer, a first optical layer positioned between the first and second metal layers, and a grating positioned on a surface of the first metal layer for coupling an electromagnetic wave into the first optical layer.

A method of magnetic recording comprising:

• creating a surface plasmon wave in a waveguide positioned adjacent to a magnetic recording pole;
• using the electromagnetic fields from the surface plasmon wave to heat a portion of a recording medium;
• and
• using magnetic flux from the recording pole to change the magnetization of the portion of the recording medium.

A planar waveguide comprising:

• a first metal layer;
• a second metal layer;
• a first optical layer positioned between the first and second metal layers;
• and
• means for coupling an electromagnetic wave to the first optical layer at a resonant incident angle.