Theoretical study of the non-parabolicity and size effects on the diamagnetic susceptibility of donor impurity in Si, HgS and GaAs cylindrical quantum dot and quantum disk: applied magnetic field influence is considered

Abstract

ABSTRACT Through this work, we have investigated the influence of the conduction band non-parabolicity (NP) and magnetic field on the diamagnetic susceptibility for a confined shallow donor impurity in a homogeneous cylindrical quantum dot (CQD) and quantum disk (QDisk); the size effect has been considered. Our calculations have been performed using the variational method which consists of the choice of a trial wave function. The Schrodinger equation has been solved within the effective-mass approximation considering the infinite height potential barrier. The numerical calculations are performed taking into account different semiconductor materials (i.e. Si, HgS and GaAs). Our results reveal that both the size and conduction band NP have a significant impact on the behaviour of the diamagnetic susceptibility for both studied systems (i.e. CQD and QDisk). It has been also noticed that, for both CQD and QDisk, the NP increases the diamagnetic susceptibility (). Furthermore, this effect is remarkable for low band gap semiconductors, especially in large QD (weak radial confinement). However, it is much more important in HgS due to its narrow band gap compared to Si and GaAs materials.