Investigation of the Structural and Thermodynamic Parameters on the Nonlinear Optical Properties of InGaAs/InP Triple Quantum Well Exposed to an External Electric Field

In this study, the effects of both tunable physical parameters and thermodynamic variables on the linear and nonlinear optical properties of the InGaAs/InP triple quantum well are theoretically investigated in detail. In addition, the effect of an external static electric field applied parallel to the growth direction of the structure was also studied. To carry out this analysis, firstly, the energy eigenvalues and eigenfunctions of the system were obtained as a result of solving the time-independent Schrödinger equation using the diagonalization method, under the effective mass and envelope function approach. Then, using these energy eigenvalues and eigenfunctions, the nonlinear optical properties of the structure were calculated from the expressions derived within the compact density matrix approach via the iterative method. The effect of adjustable structure parameters and applied external fields affects the difference in subband energy levels at which transitions occur and the magnitudes of the dipole moment matrix elements. These changes in the electronic properties of the structure cause the peak positions of the total (linear plus nonlinear) optical absorption coefficient and total relative refractive index change coefficient (RRIC) to shift towards lower or higher energy regions. These results are expected to enable the proper design of new optoelectronic devices.