首页> 美国政府科技报告 >Poling Dynamics and Effects of Trapped Charge in Poled Polymer Films forNonlinear Optical Applications
【24h】

Poling Dynamics and Effects of Trapped Charge in Poled Polymer Films forNonlinear Optical Applications

机译:非线性光学应用中极化聚合物薄膜的极化电荷的极化动力学和效应

获取原文

摘要

The behavior of surface and trapped charge that originates during contactelectric field poling of think films of optically nonlinear polymers has been investigated. Thin films of polymethylmethacrylate doped with two different tricyanothiophene chromophores have been studied during and after the poling process by simultaneous measurement of the current through the poling circuit and the second harmonic generation signal (SHG) from the polymer system. The poling current present in a fresh sample was found to differ in both magnitude and temporal dependence to that observed in the sample during subsequent polings. The magnitude of the steady state current eventually reached during the poling process was found to depend on temperature and was related to the mobility of charge. A sharp drop off in SHG signal intensity occurring when the poling electrodes were grounded is considered to be due to the removal of surface charge that orients chromophore dipoles near the surface of the film; the decay in the macroscopic polarization that the occurs is prolonged by charges trapped in the polymer matrix. The build-up of trapped charge explains a memory effect in which the SHG signal relaxation time gradually increased as the film was subjected to multiple polings. Finally, it is demonstrated that the release of charges trapped in the polymer matrix depends upon the heating rate and continues for above the glass transition temperature of the polymer.

著录项

相似文献

  • 外文文献
  • 中文文献
  • 专利
获取原文

客服邮箱:kefu@zhangqiaokeyan.com

京公网安备:11010802029741号 ICP备案号:京ICP备15016152号-6 六维联合信息科技 (北京) 有限公司©版权所有
  • 客服微信

  • 服务号