Materials

Effect of Conduction Band Non-Parabolicity on the Nonlinear Optical Properties in GaAs/Ga1−xAlxAs Double Semi-V-shaped Quantum Wells

Zhihai Zhang, Jianhui Yuan, Kangxian Guo, Elmustapha Feddi

Published Dec 26, 2018• 26 citations

Abstract

In this paper, we investigate the effect of conduction band non-parabolicity (NPBE) on the third harmonic generation(THG), the linear and nonlinear intersub-band optical absorption coefficients (OACs) related with electronic states of double semi-V-shaped GaAs/Ga1−xAlxAs quantum wells(QWs) by using the compact-density-matrix approach. Simultaneously, the work is performed in the position dependent effective mass in order to compute the electronic structure for the system by the finite difference and self-consistent techniques. We also compare the results with and without considering NPBE. It is found that: (1) the NPBE has a significant influence on the sub-band energy levels of double semi-V-shaped QWs, and (2) the amplitude and position of the resonant peaks of the THG and nonlinear OACs in the case of considering NPBE show complicated behavior due to the energy dependent effective mass m*(E) where the energy value was chosen self-consistently.

DOI: 10.3390/ma12010078

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