Characterization of Heat-Assisted Magnetic Recording Channels

The storage capacity of hard disk drives has increased tremendously over the last decade. However, the rate of increase has reached a bottle-neck as the technology approaches a theoretical limit known as the super-paramagnetic limit. Heat-Assisted Magnetic Recording (HAMR) has emerged as one of the important technologies to overcome this limit. The process of heating while writing brings about certain unique characteristics when compared to conventional schemes. In this paper, we introduce heatassisted recording, explain the techniques used to numerically model the twodimensional magnetization process in longitudinal HAMR and extend it to perpendicular recording. Utilizing these models, we investigate the transition characteristics that depend, among other factors, on various thermal parameters. In particular, we determine the effects of change in peak temperature and laser spot position on transition length and center.