摘要
从理论上研究了电子-声子相互作用对正切平方量子阱中光吸收系数的影响,首先利用微扰论方法求出考虑极化子效应时正切平方量子阱的波函数和能级,然后利用密度矩阵算符理论和迭代法得到光吸收系数的解析表达式,最后以典型的GaAs/AlGaAs正切平方量子阱为例进行数值计算。结果表明,极化子效应对线性吸收系数、三阶非线性吸收系数和总吸收系数都有显著的影响,在相同光强的情况下极化子效应使光饱和吸收现象更加明显;考虑电声相互作用后,总吸收系数的改变量随着势阱宽度b的减小和势阱深度V0的增加而增大。
The optical absorptions coefficients with considering the electron-phonon interaction were theoretically studied in square tangent quantum wells. The wave functions and energy levels are described in square tangent quantum wells by perturbation theory when the polaron effects were considered, and analytic expression for the linear and the third-order nonlinear optical absorption coefficients was obtained by the compact density-matrix method and the iterative procedure. The numerical results for typical GaAs/ A1GaAs material showed that the electron-phonon interaction had great influence on the linear, nonlinear and total optical absorption,meanwhile the absorption saturation phenomenon was more obvious than the one without considering the polaron effects. Moreover, the changes of the total optical absorptions increased with the well width b decreasing or the well depth V0 increasing when the electron-phonon interaction was considered.
出处
《量子光学学报》
CSCD
北大核心
2014年第4期331-336,共6页
Journal of Quantum Optics
基金
广东高校优秀青年创新人才培养计划(NO:LYM11077)
广东省科技计划项目(NO:2012B020313004)
关键词
吸收系数
正切平方量子阱
电子-声子相互作用
optical absorption coefficients
square tangent quantum wells
electron-phonon interaction
