FDTD Readout Analysis of a Near-Field Patterned Media Magnetooptical Recording System

Using a combination of diffraction analysis and the three-dimensional finite-difference time-domain technique, the readout behavior of a near-field magnetooptical-patterned media-based storage system incorporating a blue laser and a solid immersion lens is analyzed. It is demonstrated that the phase response of the islands themselves plays a more dominant role than the magnetization in the system readout behavior. Additionally, it is shown that, despite this characteristic, the recovery of a suitable readout signal is still possible at an island size and separation close to the system's optical limit, and also that the appearance of the readout signal is highly dependent upon the island height