Temperature-dependent anisotropic grating formation in a holographic polymer-dispersed liquid crystal

An electrically switchable Bragg grating (ESBG) recorded in a holographic polymer-dispersed liquid crystal (HPDLC) consists of alternatively periodic LC and formed polymer layers. A number of its photonic applications have been suggested so far. These include adjustable optical elements, flat panel displays, optical telecom switches/filters and tunable photonic crystals. ESBGs with large refractive index changes Deltan, low scattering loss and low switching threshold voltages are usually desired for these applications. Recently, readout-temperature dependences of first-and higher-order diffraction signal powers from ESBGs were investigated to clarify the origin of the optical anisotropy and a temperature dependence of fixed ESBGs. In this paper we report on recording-and readout-temperature dependences of the ESBG´s optical anisotropy and associated incoherent and coherent scattering. Recording-and readout-temperature dependences of the electrical switching characteristics are also described.