Transitions of the ground state and electron-electron correlations in barrier centres in magnetic fields

The relation between the electron-electron correlations and magnetic-field-induced angular momentum transitions in the barrier D- centre is investigated based on a variational method. The Chandrasekhar-type variational wavefunctions for the barrier D- states are constructed based on the exact solutions in the strong-magnetic-field limit. The energies of the barrier D- states, the binding energies, the electron densities, the angular correlations, and the average distances between the two electrons are obtained as functions of the applied magnetic field strength gamma and the distance xi between the positive ion and the plane where the two electrons reside. When the transitions of the barrier D- ground state occur for finite xi with increasing gamma, the strong correlations appear in the electron densities, the angular correlations, and the average distances between the two electrons. As a consequence of detailed considerations of the relation between the angular correlations and the strength of binding, we find that the magnetic-field-induced angular-momentum transitions occur as a result of the strong correlations in the barrier D- states.