Auger recombination in semiconductor quantum wells in a magnetic field

Abstract

Auger process involving two electrons from the conduction band and a heavy hole from the valence band in semiconductor heterostructures with quantum wells is investigated for the case of a magnetic field applied normal to heteroboundaries. It is shown that there exist three different mechanisms of Auger recombination, associated with (I) electron scattering at interface with transition into the continuous spectrum, (II) short-range Coulomb interaction in the quantum well with transition into the continuous spectrum, and (III) resonance transition into the discrete spectrum. All these processes are thresholdless. The Auger recombination coefficients analytically calculated for the processes I, II, and III show different dependencies on temperature, magnetic field, and quantum well parameters. In the limit of an infinitely wide quantum well, processes I and II merge to form a bulk threshold Auger process, while process III remains thresholdless resonance one. In the limit of infinitely weak magnetic field, process I remains thresholdless, process II becomes a quasithreshold process (i.e., its threshold energy slightly depends on temperature), and process III transforms into a nonresonance process with a threshold. The results obtained are new and have no analogies in the literature.