Optical module with multiple beams for near-field recording

High-density and high-speed have been the trend of developing next generation optical storage technologies. Rauch et al.[1] proposed a hybrid recording system called wave-guide hybrid advanced MEMS (WHAM) by using two kind of fields. One is an optical beam that controls the track width and the other is the magnetic field that controls bit length as shown in Fig. 1. The recorded mark is confined within the small cross-region and therefore the recording density is effectively increased. Kim et al.[2] further designed the module by integrating waveguide and two-dimensional toroidal optical elements into a substrate. It can be easily fabricated by MEMS technologies.