Auger lifetimes for excitons bound to deep impurities in semiconductors

Abstract

It is shown that the Auger transition probability for excitons bound to deep neutral impurities cannot be derived by extrapolating the results obtained for the series of shallow donors and acceptors. Although the probability increases with localisation over the range of binding energies characteristic of hydrogenic impurities, the breakdown of the effective mass approximation in the case of deep levels greatly reduces the Auger probability. Exceptional situations where this may not be so are also predicted.