The effect of hydrostatic pressure on metal–insulator transition in quantum well semiconductor systems

Abstract

Ionization energies of a shallow donor in a quantum well of GaAs/Ga 1− x Al x As superlattice system in the influence of pressure using a variational procedure within the effective mass approximation are obtained. The vanishing of ionization energy triggering a Mott transition is observed within the one-electron approximation. The effects of Anderson localization, exchange and correlation in the Hubbard model are included in this model. It is found that the ionization energy (i) increases as well width increases for a given pressure (ii) increases when well width increases and (iii) the critical concentration at which the metal–insulator transition occurs is increased when pressure is applied. All the calculations have been carried out with finite and infinite barriers and the results are compared with available data in the literature.