Quantum efficiency and overlap integrals in InSb

The paper deals with the problem of the enhanced quantum efficiency in semiconductors. An expression is derived for the spectral dependence of quantum efficiency in InSb in the low energy region. The probabilities both of the primary absorption process and of secondary relaxation processes, i.e. impact ionization (inter-band Auger transitions) and the thermalization of hot electrons, are calculated. The behaviour of overlap integrals in InSb is discussed in connection with these processes. The calculated spectral dependence of the quantum efficiency is compared with the experimental measurements.