Absorption enhanced media for energy assisted magnetic recording
View Patent ↗A magnetic recording media is disclosed. The media comprises a substrate, a recording layer disposed over the substrate, and a metallic layer disposed between the recording layer and the substrate. The recording layer is configured to receive an electromagnetic radiation, absorb a first portion of the electromagnetic radiation, and transmit a second portion of the electromagnetic radiation. The metallic layer comprises a non-magnetic metal and configured to reflect at least some of the second portion of the electromagnetic radiation towards the recording layer.
1. A method of enhancing energy absorption in an energy assisted magnetic recording (EAMR) media, the method comprising:
directing an incident electromagnetic energy towards the EAMR media, the media comprising a substrate, a recording layer, and a metallic layer between the substrate and the recording layer;
causing a first portion of the incident electromagnetic energy to be absorbed at a recording region of the recording layer and a second portion of the incident electromagnetic energy to be transferred to the metallic layer;
the transferred electromagnetic energy causing a surface plasmon resonance excitation in the metallic layer; and
the surface plasmon resonance excitation causing an enhanced electromagnetic absorption at the recording region.
2. The method of claim 1 , wherein the metallic layer comprises a non-magnetic metal selected from a group consisting of one or more of Au, Ag, Al, and Cu.
3. The method of claim 2 , wherein the thickness of the metallic layer is about a skin depth of the non-magnetic metal at a wavelength of the electromagnetic energy.
4. The method of claim 1 , wherein the electromagnetic absorption at the recording region is enhanced by between about 5% to 50% by the presence of the metallic layer.
5. The method of claim 1 , wherein the media further comprises an overcoat layer comprising a dielectric material having a refractive index greater than 1.5.
6. The method of claim 5 , wherein the dielectric material is AlN or Si 2 N 4 .