Electric-field effects on shallow impurity states in GaAs-(Ga,Al)As quantum wells

Abstract

The inhuence of an applied electric field on shallow donor and acceptor states in GaAs-(Ga, Al)As quantum wells is studied. We work within the effective-mass approximation and adopt a trial envelope wave function for the impurity carrier, which leads to the exact results for vanishing applied electric fields and limiting values of the quantum-well thickness. Results for the binding energies and density of impurity states as functions of the impurity position, well thicknesses, and applied electric field are reported. Some results for the effects of electric field on the donor-related optical properties are also presented. As a general feature, the density of impurity states and impurityrelated optical absorption for finite electric fields exhibit three van Hovelike singularities corresponding to the binding energies associated with impurities at the two edges of the quantum well and at the position at which the binding energy has a maximum.

Donor‐related density of states and polarizability in a GaAs‐(Ga, Al)As quantum‐well under hydrostatic pressure and applied electric field

“…The main feature is the presence of three peaks, as in the case of applying only an electric field, slightly shifted by the applied pressure. The applied electric field breaks the well mirror symmetry [10,11] and produces an unsymmetrical electron binding energy as a function of the impurity position leading to a three-peak DOIS. The further application of a hydrostatic pressure moves the peak structure to higher energies.…”

“…(1) without the impurity potential term at the right (with eigenvalue E 0 ) and the 1s-like hydrogenic wave function [10,11].…”

“…Such effects may introduce considerable changes in the energy spectrum of the carriers, which could be used to control and modulate the output of optoelectronic devices [10,11]. Through the wave function, the polarizability measurements shed light on the dynamics of the carriers and optical properties in low dimensional heterostructures [12][13][14][15][16].…”

Symmetric and asymmetric GaAs/Al0.3Ga0.7As double quantum well subjected to hydrostatic pressure and applied electric field

“…1 we present the potential model we use in our calculations. The potential profile in the barriers is taken as a constant value because our results are for the internal screened electric field [15].…”

Mixing of impurity levels by a built‐in electric field in a CdMgTe/CdZnTe heterostructure

“…Introducing a δ layer of impurities in different places of a quantum well or a superlattice is an example of such an approach [1,2]. External magnetic (B) and electric fields (E) that lower the symmetry of a system serve as additional perturbations allowing one to reveal fine details of an impurity environment [3,4].An interface is a particularly interesting and important part of a quantum structure. Recently, properties of interfaces have been re-examined in connection with optical in-plane anisotropy of asymmetric quantum wells of zinc-blende structure [5,6].…”