施加电场的半抛物量子阱中的电光效应(英文)

Influences of Electric Field on Electro-optic Effects in aSemi- Parabolic Quantum Well

利用量子力学中的紧致密度矩阵方法,研究了施加电场的半抛物量子阱中的电光效应。通过位移谐振子变换,得到了系统中的电子态的精确解。对典型的GaAs材料进行数值计算的结果表明,随着电场强度的增加,电光效应系数几乎线性随之增加;但是随着半抛物量子阱受限势频率的增加,电光效应系数单调地减小;而且在同样的电场强度及抛物束缚势频率作用下,半抛物量子阱模型中的电光效应系数比抛物量子阱模型中的值大两个数量级,这是由于我们所选模型本身的非对称性以及电场进一步使这种非对称性增强的缘故。

?By using the compact density matrix approach, the electro-optic effect (EOE) in a semi-parabolic quantum well (QW) with an applied electric field has been theoretically investigated. Via variant of displacement harmonic oscillation, the exact electronic states in the semi-parabolic QW with an applied electric field are obtained. Numerical results on typical GaAs material reveal that electro-optic effect nearly linearly increases with the increasing of magnitude of the electric field, but it monotonously decreases with the increasing of confined potential frequency of the semi-parabolic QW. The EOE in our model is 102 times larger than that in the symmetric parabolic QW under the same electric field and the same frequency of parabolic confined potential, which is due to the self-asymmetry of the system and the electric field effect.