Ge_(27)In_8S_(65)玻璃的超快三阶非线性光学性质研究

Ultrafast Third-order Optical Nonlinearity of the Ge_(27)In_8S_(65) Glass

根据传统的熔融淬冷技术制备了Ge27In8S65硫系玻璃样品。根据该玻璃的可见-近红外光谱知,其可见截止波长为560 nm。由椭偏仪测得该玻璃在820 nm处的折射率为2.21。利用超快飞秒时间分辨光克尔门技术表征了Ge27In8S65玻璃在820 nm处的超快三阶非线性光学性质。根据同一试验条件下与标样(CS2)克尔信号强度比IS/IR(0.96)可推算出Ge27In8S65玻璃三阶非线性极化率χ(3)的大小为1.9×10-13esu;根据Ge27In8S65玻璃克尔响应曲线轮廓可知其超快非线性响应过程基本上是瞬时的,主要由玻璃微结构基团电子云的扭曲所产生。

The Ge27In8S65 chalcogenide glasses were prepared by the conventional melt-quenching technique. The visible absorption edge of the present glass was measured to be located at 560 nm in terms of the visible-near infrared spectrum, According to the dispersive curve of refractive index obtained by an ellipsometer, the refractive index of the present glass was 2.21, The ultra fast third-order optical nonlinearity of the Ge27 In8S65 chalcogenide glass was investigated utilizing the femtosecond time-resolved optical Kerr gate system. The third-order nonlinear susceptibility was estimated to be 1.9 × 10^- 13 esu. The Kerr signal had symmetric Gaussian profile which was mainly attributed to the nonlinear response of the deloealized electrons.