$D^-$-center energy spectrum in a quantum constriction given the electric and magnetic fields

In the framework of the model of zero-radius potential the authors theoretically investigate the $D^-$-states in a quantum constriction given the external longitudinal axis contraction, the electric and magnetic fields. The article describes the obtained dispersion equation of the electron localized on the $D^-$-center and examines its dependence on the effective length of the constriction, the coordinate values of the impurity and the tensions and the magnetic induction of external fields.