Photoinduced Birefringence in Poly(malonic ester) Containing p-Cyanoazobenzene with Photoexcitation of cis Conformer
Photoinduced Birefringence in Poly(malonic ester) Containing p-Cyanoazobenzene with Photoexcitation of cis Conformer
复制标题
顺式构象光激发下含对氰基偶氮苯的聚丙二酸酯的光致双折射
DOI：
10.1021/jp0102825
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发表时间：
2001
影响因子：
3.3
通讯作者：
Yang
中科院分区：
文献类型：
--
作者：
Won;C. Oh;S. Song;P. Kim;Yang
用波长分别为365和488 nm的泵浦光研究了含两个对称对氰基偶氮苯基团的聚丙二酸酯的光致双折射。我们观察到意想不到的光致双折射，甚至由488 nm的泵浦光作为大的365 nm。为了描述这种特殊现象，我们通过一种新的实验装置测量了诱导双折射的大小和方向，在聚合物薄膜和传统一对交叉偏振器装置的检偏器之间添加了1/4波片。用365和488 nm的两束垂直偏振光束同时照射的光致相位延迟的测量支持了这样一个事实，即除了典型的反-顺光异构化偶氮苯的光致双折射还有另一个过程。
Photoinduced birefringence in a poly(malonic ester) containing two symmetrical p-cyanoazobenzene groups has been investigated using two pumping beams with different wavelengths of 365 and 488 nm, which are assignable to the absorption wavelengths of trans and cis conformers of azobenzene, respectively. We observed unexpected photoinduced birefringence even by the pumping beam of 488 nm as large as that by 365 nm. To describe such specific phenomenon, we measured the magnitude and direction of the induced birefringence by means of a new experimental setup, adding I/4 waveplate between the polymer film and the analyzer of conventional a pair of crossed polarizers setup. The measurement of the photoinduced phase retardation by simultaneous illumination with two perpendicularly polarized beams of 365 and 488 nm supports the fact that there is another process for the photoinduced birefringence besides a typical trans -cis photoisomerization of azobenzene.