Thermal Modeling of Optical Power Absorption in Moving Multilayer Thin Films

Abstract

Abstract:A technique for computing the thermal profile in a multilayer moving medium is described. This technique is particularly suitable for studying the near field optical/thermal interplay in hybrid optical/magnetic recording because the boundaries of the computation space are effectively removed from the optical source. It is shown that a three layer medium can be designed with a thermal time constant which is suitable for high recording data rates and that minimizes the thermal bloom from motion of the medium with respect to the optical spot. However, the thermal spot is much larger than the optical spot which leads to a reduced storage density.

Noise Mitigation in Granular and Bit-Patterned Media for HAMR

“…The optical fly height is 8 nm. Instead of an average thermal conductivity for the cells at the interface [16], an effective thermal conductivity κ eff shown in (2) is used in our calculation. The power absorption for each cell varies with time when the optical head moves along the down-track direction.…”