Simulation of magnetic footprints for heat assisted magnetic recording

Abstract

The heat assisted magnetic recording (HAMR) technology has been the promising candidate to overcome the thermal stability limitation at higher capacities of the hard disk drive. In this work, the characteristics of magnetic footprint of the medium written by HAMR were investigated through the micromagnetic simulations. The Voronoi granular media was firstly modeled, then the magnetic footprint technique was performed to observe the media behaviors at various linear densities. The results indicated that the pattern of magnetic footprint can be perverted at higher densities, which essentially causes a reduction of readback signal power. Also, the dependence of media grain size on the signal power shows that the larger grain size media can provide higher signal power at low linear density, while the smaller grain size media gives higher signal at high density. Thus, the magnetic footprint regarding the HAMR technology needs to be optimized to achieve the efficient recording system.