Domain Edge Formation and Jitter Characteristics in Thermomagnetic Recording with Magnetic Field Modulation

Abstract

The role of the dynamics of the magnetic bias field in field modulation thermomagnetic recording has been studied experimentally and through computer simulation. Using a continuous-wave, focused laser to heat a Magnetooptic recording medium, we varied the magnitude and the spatial gradient of the modulated bias field, and measured the behavior of medium noise and jitter in Magnetooptic recording. The experimental measurements yielded a universal curve for the relation between signal pulse jitter and the spatial gradient of the recording bias field. Micromagnetics simulations provided insight into the connection between bias field magnitude and its spatial gradient and the degree of domain wall irregularity in recorded marks. This work suggests directions for the optimization of field modulation direct overwrite recording in Magneto-optical data storage. © 1990 IEEE