The effect of pressure, temperature and Al concentration on linear and nonlinear optical properties of symmetric and asymmetric double triangular quantum dots

This study theoretically investigates the linear and third-order nonlinear optical absorption coefficients and relative refractive index changes in symmetric and asymmetric double triangular potential-shaped spherical quantum dots. We examine the effects of temperature, pressure, and aluminum concentration on these optical properties. Using the compact density matrix approach and iterative procedure, we derive analytical expressions for the linear and nonlinear optical properties, with energies and wave functions calculated within the effective mass and parabolic band approximations. Numerical results are presented for a typical GaAs/AlGaAs material system. The findings reveal distinct influences of temperature, pressure, and Al concentration on the optical properties, with differences in resonance frequency and nonlinear contributions between symmetric and asymmetric structures. These results demonstrate that hydrostatic pressure, temperature, and Al concentration significantly affect the electronic and optical properties of double triangular quantum dots, enabling the tuning of optical responses and optimization of inter-subband transitions for optoelectronic applications.