Change Of Symmetry Of The Barrier D- Ground State In Finite Magnetic Fields

The states of the barrier D- center which consists of a positive ion located on the z axis at a distance from the x-y plane and two electrons in the same plane bound by the ion are investigated based on a direct diagonalization method in finite and relatively high magnetic fields. The energies of the barrier D- states, the binding energies for the barrier D- states, and the expectation values of both the distance of the electron from the origin and distance between two electrons are obtained as functions of the applied magnetic field strength gamma perpendicular to the x-y plane and the distance zeta between the positive ion and the x-y plane. The effects of the higher Landau levels become small as gamma and zeta increase. The change of symmetry of the barrier D- ground state is possible in finite magnetic fields. Both the distance of the electron from the origin and distance between two electrons vary discontinuously with the changes of symmetry of the barrier D- ground states. Our calculations indicate that the phase transitions of the barrier D- ground states can be observed in real systems.