Density-Functional Approach to the Metal-Insulator Transition in Doped Semiconductors

Abstract

To describe the metal-insulator transition in doped semiconductors, we have worked out a model which incorporates electron-electron interactions through the Kohn-Sham density-functional scheme within the cellular approximation. The vanishing of the conductivity activation energy, the impurity-band formation, and the change from spin-polarized localized states to unpolarized extended ones are accounted for. We predict these states to coexist in a narrow temperature and concentration range.