摘要
二阶非线性光学聚合物是最有希望实现在电光器件方面应用的材料之一.该类材料的非线性光学系数很高, 响应速度快, 与半导体材料的相容性较好, 且比有机和无机晶体的制备更方便[1,2].
A novel cross-linked polyurethane with high second-order nonlinear optical(NLO) activity and high thermal stability was synthesized from disperse Red-19 and the trimer of 2,4-toluene diisocyanate. The electro-optical coefficient(r33) of the polyurethane and the electro-optical modulation efficiency of the spatial modulator were measured at lasers of 632, 650, 832 and 980 nm by the improved attenuated-total-reflection technology after the polyurethane was poled and cured. The results indicate that r33 and the modulation efficiency increase in the absorption region of the polyurethane with the descending of the incident laser wavelength. Further theoretical and experimental researches show that the enhancement of the electro-optical effect is resulted from the complex refractive index change. The change increased with the ab-sorbance of the polyurethane due to the resonance of the NLO polyurethane and the incident laser. As a result, for spatial electro-optical(EO) modulator like attenuated-total-reflection EO modulator, the absorption region can be effectively utilized notonly because the effective optical path length is much shorter that of a waveguide EO modulator and optical losses do not present a serious problem but also because the electro-optical effect will be strengthened by the resonance.
出处
《高等学校化学学报》
SCIE
EI
CAS
CSCD
北大核心
2003年第9期1683-1685,共3页
Chemical Journal of Chinese Universities
基金
国家自然科学基金(批准号:50073005)
关键词
二阶非线性光学
聚氨酯
电光效应
共振增强
折射率
Second-order nonlinear optics
Cross-linked polyurethane
Electro-optical effect
Resonance enhancement
