電光活性高分子薄膜之第二級非線性光學特性之研究

Abstract

二次非線性光學訊號已被運用來研究非線性光學分子的排列分佈情形及第 二階非線性光學特性.本論文中選擇兩種不同系列的高分子:側鏈型高分子 及半交互滲透型高分子.藉由量測其在電暈極化過程下的二倍頻訊號,薄膜 溫度和電場大小來探究其非線性光學分子的排列分佈,並觀測其二倍頻訊 號在不同溫度下的衰減曲線以研究它們的熱穩定性.所獲得的資訊不僅有 助於改善二次非線性光學效應,也可以幫助我們洞察高分子材料有序排列 的熱穩定性. Optical second-harmonic generation(SHG) has been applied to investigate the second-order nonlinear optical(NLO) properties and the orientational distribution of NLO chromophores.Two types of NLO polymeric systems have been selected for this study, which includes side-chain polymer and semi- interprnrtration polymer network. The orientational distribution of NLO chromophores e these polymeric systems during corona poling was probed bying the optical second- harmonic signal, film temperature and electric poling field simultaneously. The decay curves of the SHG intensity in several different temperatures were measured toeal their thermal stability. The information yieled was found to be usefully not only for improving the second-order nonlinear optical(NLO) response, but also providing insight in the thermal stability of the poled order in these polymeric materials.