Polarization holographic grating based on azo-dye-doped polymer-ball-type polymer-dispersed liquid crystals

Abstract
A polarization grating (PG) written in an azo-dye-doped film of polymer-ball-type polymer-dispersed liquid crystals was investigated. The writing beams were two mutually orthogonal (s- and p-polarized) polarized beams. The PG resulted from molecular reorientation of the liquid crystals as a result of their interaction with the dye molecules adsorbed on the surface of the polymer balls. Polarization characteristics of the diffracted beams and the grating pattern were studied under a polarizing optical microscope with a crossed analyzer. The results indicate that the PG diffracts the linearly polarized incident light into beams with various polarizations. Accordingly, the grating can be used as an unpolarized or a polarized beam splitter, depending on the polarization of the incident light. A model based on the Jones matrix approach was developed, and it closely fits the experimental results.