Nonlinear photoexcitation of heterostructures with deep quantum wells: I. Probabilities of elementary processes

The probabilities of different types of optical processes involved in the formation of a photon avalanche in type-I heterostructures with deep quantum wells are calculated. The processes include two-electron transitions with participation of a photon, phototransitions between electronic states of size-quantized subbands and continuum of band states, and two-photon interband transitions in quantum wells. The obtained probabilities will be used in the forthcoming parts of the study for analysis of photon-avalanche kinetics.