Abstract The periodic oscillation of the optical transmittance in the nematic liquid crystals (5CB) doped with azobenzene compound (DR1) between two crossed polarizers has been demonstrated and investigated by monitoring the signal intensity variation of the transmitted light in different conditions of the light irradiation and environment temperature. It is found that the oscillation of the transmittance lasts more than 4 periods before the nematic–isotropic phase transition when the dye doped liquid crystal sample is heated from 20 to 40 °C. The oscillation is attributed to the continuous decrease of the birefringence of the dye doped liquid crystals with the temperature increasing. The oscillation curve shifts forward significantly when the sample is exposed to the pump light irradiation, which indicates that the pump light irradiation induces an additional decrease of the birefringence. A more accurate and comprehensive way for estimating the magnitude of the birefringence of the anisotropic materials is proposed based on the transmittance oscillation phenomenon. The switchable properties and the potential applications of the transmittance oscillation are discussed.

中文翻译：

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偶氮染料掺杂液晶在两个交叉偏振器之间的光学透射率的周期性振荡

摘要 通过监测不同光照射条件下透射光的信号强度变化，证明并研究了掺杂偶氮苯化合物 (DR1) 的向列液晶 (5CB) 在两个交叉偏振器之间的光学透射率的周期性振荡。环境温度。发现当掺杂染料的液晶样品从 20 到 40°C 加热时，透射率的振荡在向列 - 各向同性相变之前持续超过 4 个周期。振荡归因于染料掺杂液晶的双折射随着温度的升高而不断降低。当样品暴露在泵浦光照射下时，振荡曲线显着向前移动，这表明泵浦光照射引起双折射的额外降低。基于透射率振荡现象，提出了一种更准确、更全面的估计各向异性材料双折射大小的方法。讨论了透射率振荡的可切换特性和潜在应用。