Multistate polarization addressing using a single beam in an azo polymer film

Opt Lett. 2005 Aug 1;30(15):1986-8. doi: 10.1364/ol.30.001986.

Abstract

Peculiar light-matter interactions can break the rule that a single beam polarization can address only two states in an optical memory device. Multistate storage of a single beam polarization is achieved using self-induced surface diffraction gratings in a photoactive polymer material. The grating orientation follows the incident light beam's polarization direction. The permanent self-induced surface relief grating can be read out in real time using the same laser beam.