Electron and hole energy levels in InAs/GaAs quantum dots: Size and magnetic field effects

Abstract

We present a systematic study on the influence of strain, size, and magnetic field on the electronic properties of InAs/GaAs quantum dots. Using a 40-band k.p model, we have calculated the band diagram of strained InAs, and extract the band parameters which are useful for the electronic properties of InAs/GaAs quantum dots. Then, using an exact numerical diagonalization method on Fourier–Bessel function basis over a large cylinder domain, we calculated numerically the electron and hole eigenenergies and associated wave functions. We considered thereafter the effect of an external applied magnetic field, strain and quantum dot size variation on the charge carrier energy levels. It is clearly found that the strain strongly modifies the quantum dot potential profile, leading to a different electron and hole energy distribution. Our results revealed also that the electron and hole energy spectra change significantly when varying the quantum dot size as well as the magnetic field. Given this striking nanostructure size and magnetic field energy dependent property, these systems provide the opportunity to control and tune their optical and electronic properties through these parameters.