The properties of 3 spatial configurations of D- centers in GaAs-based structures were studied by using a numerical technique for the solution of the 2-electron Schrödinger equation. Results for the quantum well, Dw-, were compared with experimental data and with variational and Monte Carlo calculations. The existence of the spatially separated Ds- center as a bound state was demonstrated; even in very weak magnetic fields. Interesting anti-crossings among the energy levels in its electronic structure were found which underlay a spectrum that comprised a D0 donor center and a free electron in a magnetic field. In the case of the remote Dr- center, it was found that strong electron-electron correlations could give rise to magnetic field-induced angular momentum transitions.

I.K.Marmorkos, V.A.Schweigert, F.M.Peeters: Physical Review B, 1997, 55[8], 5065-72