On the theory of electronic processes in ionic crystal semiconductors

Electronic processes of impurity centers in ionic crystals are discussed. The crystal is divided into an ensemble of microblocks each containing one impurity in its center. The microblocks surrounding a single microblock act like a heat reservoir. The Hamilton operator of the total system is composed of the energy of the microblock, the radiation field, the heat reservoir, and the mutual interaction energies. The base system is assumed to be a product of the wave functions of the subsystems. For the electrons a Hartree-Fock ansatz is used which is reduced to an energy functional of the impurity center electrons. For the lattice wave functions dressed phonon states are introduced. The electron-phonon coupling is calculated and stochastic equations for radiative and nonradiative electronic processes are derived. The transition probabilities depend on the dressed-phonon resonances.