Plasmon antenna with magnetic core for thermally assisted magnetic recording

摘要

A TAMR (Thermal Assisted Magnetic Recording) write head uses the energy of optical-laser generated plasmons in a plasmon antenna to locally heat a magnetic recording medium and reduce its coercivity and magnetic anisotropy. To enable the TAMR head to operate most effectively, the maximum gradient of the magnetic recording field should be concentrated in the small region being heated. Typically this does not occur because the spot being heated by the antenna is offset from the position at which the magnetic pole concentrates its magnetic field. The present invention incorporates a magnetic core within a plasmon antenna, so the antenna effectively becomes an extension of the magnetic pole and produces a magnetic field whose maximum gradient overlaps the region being heated by edge plasmons being generated in a conducting layer surrounding the antenna's magnetic core.