溶剂对光致变色材料-乙基红的光学特性影响

研究了溶剂性质对光致变色材料乙基红光学性质的影响.用吸收谱测定了乙基红染料在不同溶剂中的溶剂化位移.对相同浓度多种乙基红溶液进行了Z-scan测量，测量了不同乙基红溶液的光限幅效应，并讨论了其与溶剂之间的关系.随极性增加，吸收谱蓝移，可以通过选择不同溶剂，改变非线性材料的应用窗口.实验结果表明，在连续光照射下，乙基红溶液的非线性折射主要由热效应引起，非线性折射系数n2受溶剂的热学性质影响较大.此外，Z-scan结果中的非线性吸收为饱和吸收.至于光限幅效应，主要受热效应影响，但亦可由吸收谱预测出在某波长处的动态范围.得出的结论有助于偶氮染料作为非线性材料的应用.

The Influence of Solvent on Optical Performances of Photochromic Materials-ethyl Red

The influence of solvent effect on optical performances of photochromic material ethyl red has been studied.The solvent induced changes of absorption spectra of ethyl red solutions are measured. The nonlinear optical properties of different solution layers of ethyl red and their optical limiting are measured by Z-scan. The relations between Δα and properties of solvents are discussed.It is found that with the increasing of polarity of solvents, the absorption spectra are blue shift, so the application “window” of the nonlinear material can be changed by choosing different solvents.The experimental results show that the nonlinear refraction of dye irradiated by cw laser is mainly caused by the thermal effect,and the influence of thermal character of solvents to n_2 is relatively great.Furthermore,the nonlinear absorption in Z-scan result is saturable absorption,which mainly caused by polarities of solvents.As far as optical limiting effect is also induced chiefly by thermal effect,its dynamic range of the optical......