Effects of external electric and magnetic field on the nonlinear optical rectification, second, and third-harmonic generations in GaAs/AlGaAs asymmetric triple quantum well

In this paper, we theoretically investigate the nonlinear optical rectification (NOR), second-harmonic generation (SHG), and third-harmonic generation (THG) coefficients of an AlGaAs/GaAs asymmetric triple quantum well structure under external electric and magnetic fields. To do this, we first obtain the solution of the time-independent Schrodinger equation numerically using the diagonalization method under the effective mass approximation to obtain the subband energy levels (with related wave functions) of the heterostructure. We then use the compact density matrix method to form the mathematical expressions of NOR, SHG and THG coefficients. The numerical results from our investigation show that the resonance peaks of the NOR, SHG and THG coefficients shift to a high energy (low energy) region with an increase in the magnitude of the electric (magnetic) field. As a result, we believe that numerical results obtained from carried out our parameter analyzes will present important developments and provide great contributions in designing new optoelectronic devices related asymmetric triple quantum well structure.