记录光偏振对掺偶氮染料液晶薄膜二波耦合效应的影响

研究了平面型掺偶氮染料(DR1)向列液晶(5CB)薄膜对可见光波段的响应及在二波耦合实验中探测光(633nm)的衍射效率与记录光(488nm)偏振的关系,并进行了相应解释,得到了小角度入射条件下,记录光偏振方向平行于样品摩擦取向方向时的空间变化的介电张量。此结果适用于多数偶氮类染料,很好地解释了光致顺-反异构引起的折射率变化。

Dependence of Two-beam Coupling Effects on Polarization of Recording Beams in Azo-dye-doped Liquid Crystal Film

The visible spectral response and the dependence of the diffraction efficiency of probe light (633 nm) on polarized pump light at a two-beam coupling in the planar Disperse Red 1 (DR1)-doped sample have been observed. An analysis is presented. A spatially varying dielectric tensor is obtained in the case of a small recording angle when the polarization direction of the recording beams is parallel to the director vector of the sample. This result may explain the index change induced by trans-cis isomerization in most of azo-dye-doped liquid crystal films.