Figures of merit for recordable optical media

A variety of figures of merit (FOM) have been proposed for magneto-optic media design. The Lissberger limit is particularly useful for making comparisons between different magnetooptic materials. It can predict, for instance, the maximum signal for an optically optimized film stack. The derivation of this FOM also determines the film stack design which optimizes the MO signal. In this paper we develop the corresponding FOM for phase change media. We also present a comparison of the FOM calculation with film stacks optimized by computer modeling for GeTeSb.