The nonresonant transfer of energy between impurities in solids

The nonequilibrium statistical operator method is used for theoretical investigation of nonresonant transfer of energy between impurities in solids in cases when energy migration between donors occurs during a time much less than the transfer time. Apart from subsystems of donors, acceptors and the vibrational quanta participating in the process under consideration (which may be intramolecular vibrations or phonons), we introduce the so-called dipole-dipole reservoir, which exerts an essential influence on the energy transfer kinetics. Various limiting cases are investigated. The saturation of donors by light pulses may lead to an avalanche-like increase of the number of vibrational quanta.