Holographic approach to store binary data densely beyond the Rayleigh limit using near-field scanning optical microscopy

摘要

We propose a holographic method for the storage and retrieval of sub-Rayleigh-limit-size binary data using near-field scanning optical microscopy (NSOM). The experimentally retrieved spot size was smaller than 200 nm (the wavelength of light source is 633 nm), which shows our scheme can record binary data densely beyond the Rayleigh limit. In addition, our scheme can store multiple data in the same physical space with the conventional multiplexing methods, which enables the ultra-high-density optical memory system. Experiments on angular multiplexing show that the angular selectivity was about 0.01 degree.