Coexistence of Itinerant Electrons and Self-Trapped Electrons

Abstract

The ground-state properties of the low-density electron system with the short-range electron-phonon interaction is investigated theoretically in connection with the self-trapping of an electron. The energy change of the system due to lattice distortions is calculated with the use of Fumi’s theorem and the coherent potential approximation. It is shown that the itinerant electrons and the self-trapped electrons coexist in a certain range of the parameters.