Stability Analysis of Exciton, Charged Excitons, and Biexciton in an Inp/Gaas/Gasb Type-II Quantum Dot Heteronanostructure: A Comparison of Binding Energy and Diamagnetic Susceptibility

Abstract

The present study focused on investigating the total energies, binding energies, and diamagnetic susceptibilities of excitons, negative and positive trions, and biexcitons within an InP/GaAs/GaSb type-II quantum dot heteronanostructure. The analysis has been carried out by varying the InP core radius, GaAs and GaSb layer thicknesses, and temperature. To obtain the energy levels and wavefunctions of the system, the Poisson-Schrodinger equation has been solved under the effective mass approximation and BenDaniel-Duke boundary conditions, considering the dielectric mismatch. The results of the calculations have revealed that while diamagnetic susceptibility could provide reliable information about the stability of the exciton, it has not offered the same level of accuracy when assessing the stability of the negative and positive trion and biexciton. Additionally, it has been observed that the dielectric mismatch effect can be influential, to the extent of reversing the expected trend in the binding energy, particularly when the GaAs layer thickness varies. On the other hand, the effect of temperature has been found to be limited and negligible due to the strong confinement of the quantum dot heteronanostructure.