Simulation of expected areal density gain for heat assisted magnetic recording

Areal density increases in conventional perpendicular magnetic recording are becoming increasingly difficult to achieve. Heat assisted magnetic recording is viewed as a potential technique to extend magnetic recording into the multiple-terabit range. Over the last 5 years, we have performed extensive simulations of Heat Assisted Magnetic Recording on both granular and bit-patterned media. For this purpose, we represent the behavior of granular media near the Curie temperature with renormalized blocks of spins of order 1 nm³. The change in magnetization of these blocks can then be evaluated using the Landau-Lifshitz-Gilbert equation. The behavior of bit patterned media is typically evaluated using an atomistic approach. Optical spots are calculated using a finite difference time domain technique and heat flow is evaluated using the usual Fourier differential equation. We have also evaluated the performance of competing technologies including both conventional and shingled recording of both granular and bit patterned media.