兩種鐵電性液晶之二次諧波產生特性研究

Abstract

我們以飛秒雷射照射由兩種不同的鐵電性液晶製成之樣品，並在 雷射光束的透射方向量測不同入射角之下的二次諧波產生訊號。

藉由觀察置於正交偏振片下的樣品，構思了混何域和隨機域的模型及其訊號分析方法。並藉由改變入射光的偏振態並測量不同篇振下的倍頻光訊號。得到了香蕉型鐵電性液晶分子兩個非線性係數的比值，分別是在-1.55至-1.215間和-2.034至-2.931間。

We use the femtosecond laser to irradiate the samples made of two different frerroelectric liquid crystals. The transmission second-harmonic generation signals with different angle of incidence, and measured.

We have constructed the models of “mix domain” and “random domain” according to the textures of the sample between crossed polarizer which observed under the microscope and measured data. By changing the polarization of the incidence beam, and measure different polarized double frequency signals, we get the ratio of the two different nonlinear coefficients of banana-like frerroelectric liquid crystal, which are about -1.55 to -1.215 and -2.034 to -2.931 respectively.