双曲型量子阱中非线性光学吸收率的计算  

Intersubband optical absorption in hyperbolic quantum wells

作　　者：谭鹏[1] 路洪[1] 

机构地区：[1]佛山科学技术学院理学院物理系,广东佛山528000

出　　处：《量子电子学报》2007年第1期80-84,共5页Chinese Journal of Quantum Electronics

基　　金：Support by the Natural Science Foundation of Educational Department of Guangdong Province(06029431)

摘　　要：量子阱中的非线性光学效应因其潜在的实用价值而引起了人们的广泛的关注,而量子阱内带间的光学吸收问题对研究远红外光学探测器等光电子器件具有重要的理论指导意义.用量子力学中的密度矩阵算符理论导出了双曲型量子阱中的线性与三阶非线性光学吸收系数的表达式．因双曲型量子阱中有一个可调参数。随着参数的增加,阱宽将相应增加,因此势阱的形状以及阱内的非线性光学吸收率将随参数变化而发生规律性的变化,并且当入射光强增强到一定程度会出现较强的饱和吸收现象,通过对这些规律的研究从而为实验研究提供了必要的理论依据。The problem of optical saturation of intersubband absorption has attracted considerable attention recently. The problem is very important to the development of superlattice devices such as fast infrared detectors and modulators because one needs to know the range of input optical intensities for which linear operation is possible. The linear and the third-order nonlinear optical intersubband absorption coefficients in hyperbolic quantum wells are studied, where emphasis is devoted to the influence of the shape of the wells on the absorption coefficients. The analytic forms for the linear and the third-order nonlinear optical intersubband absorption coefficients are derived by means of the density matrix formalism taking into account the intrasubband relaxation. Finally, the numerical results show that the optical absorption coefficients depend on the shape of the wells, the tunnel bandwith and the optical intensity.

关 键 词：非线性光学 双曲型量子阱 吸收系数 密度矩阵方法 

分 类 号：O437.1[机械工程—光学工程]