THE SYMMETRY OF DONOR-BOUND ELECTRON WAVE-FUNCTIONS IN QUANTUM-WELLS

In order to investigate the symmetry (i.e. sphericity) of donor-bound electron wavefunctions in quantum wells, we have invoked a two-paramet er trial wavefunction. One parameter is the Bohr radius lambda, whilst the other is the eccentricity parameter zeta. The latter incorporates the effect of the quantum well (QW) on the carrier motion in the grow th (i.e. the z) direction. Working within the envelope function approx imation it is shown that the donor wavefunction has the form of a prol ate spheroid. However, calculations of the ratio lambda/zeta shows tha t it is the value of lambda which determines the essential symmetry of the wavefunction. (C) 1998 Academic Press Limited.