Optical properties of a two-dimensional GaAs quantum dot under strain and magnetic field

Abstract

It is well known that the use of the strain plays an important role in the material properties. Strain effect is a potential tool for altering the atomic positions and defect formations. It can adjust the electronic structures and lattice vibrations. It can also affect the phase transition of the structure, the physical and chemical properties. Consequently, in this paper, we have studied the effects of strain and magnetic field on optical properties of a two-dimensional quantum dot. The Hamiltonian of our system consists of the Bychkov–Rashba, Dresselhaus and strain-dependent terms. Using the diagonalization method, we have obtained the energy levels and wave functions of the system and thereby the refractive index changes and absorption coefficient in the presence of different strains. According to the results, it is found that an anti-crossing magnetic field is 7.37 T and it does not depend on the strain. Also, the energy transition increases with enhancement in the strain and decreases with increase in the magnetic field. The refractive index changes and absorption coefficient shifts toward lower (higher) energies for negative (positive) strain. The energy transition has lower values for negative strain at fixed magnetic field and confinement length.