paper

Kinetic Monte Carlo Simulations of a Model for Heat-assisted Magnetization Reversal in Ultrathin Films

arXiv:1105.5155 · doi:10.1103/PhysRevB.84.094431

Abstract

To develop practically useful systems for ultra-high-density information recording with densities above terabits/cm, it is necessary to simultaneously achieve high thermal stability at room temperature and high recording rates. One method that has been proposed to reach this goal is heat-assisted magnetization reversal (HAMR). In this method, one applies a high-coercivity material, whose coercivity is temporarily lowered during the writing process through localized heating. Here we present kinetic Monte Carlo simulations of a model of HAMR for ultrathin films, in which the temperature in the central part of the film is momentarily increased above the critical temperature, for example by a laser pulse. We observe that the speed-up achieved by this method, relative to the switching time at a constant, subcritical temperature, is optimal for an intermediate strength of the writing field. This effect is explained using the theory of nucleation-induced magnetization switching in finite systems. Our results should be particularly relevant to recording media with strong perpendicular anisotropy, such as ultrathin Co/Pt or Co/Pd multilayers.

8 pp., 7 figs

References in corpus (1)

Cited by in corpus (11)