Plasmon resonator with dual waveguide excitation for TAMR

摘要

A TAMR (Thermal Assisted Magnetic Recording) write head uses the near field energy of optical-laser excited plasmon eigenmodes in a plasmon resonator to locally heat a magnetic recording medium and reduce its coercivity and magnetic anisotropy. The plasmon resonator is formed as a conducting disk-shaped structure with an extending peg that serves to further confine the near fields within a small region of the recording medium. The resonator eigenmodes are excited, through direct or evanescent coupling, by an interference pattern formed by the overlap of optical waves within a dual-channel waveguide, the interference pattern being the result of the waves in one branch being phase-shifted relative to the waves in the other branch.

主权项

1. A TAMR (thermally assisted magnetic recording) head having an ABS end, comprising:
a magnetic write pole which, when energized, produces a magnetic field for writing on a magnetic recording medium rotating beneath said ABS end; a source of electromagnetic radiation mounted on said head or external thereto; a double-branched waveguide, wherein said waveguide accepts said radiation in a single waveguide portion and creates a travelling mode of said radiation in each of two branches and directs each of said modes towards a plasmon resonator located at said ABS end; wherein a phase difference created between each of said travelling modes of said electromagnetic radiation is capable of producing an interference field of said electromagnetic radiation at the location of said plasmon resonator; wherein terminal ends of said branches proximal to said ABS end are bent at an angle and directed at said plasmon resonator to thereby produce said interference field; and wherein said terminal ends of said branches are merged or are separated; and wherein said electromagnetic radiation is directly or evanescently coupled to plasmon eigenmodes within said plasmon resonator, whereby near field portions of said plasmon eigenmodes impinge on said magnetic recording medium.