Theoretical study of Auger effect in 1.5 μm quantum-well lasers

Abstract

A new methodology for the derivation of the Auger recombination rate in quantum wells is presented. An expression of the Auger recombination rate is given, taking into account a realistic valence band structure, the Fermi–Dirac statistics, and the analytic expressions of the transition matrix element for both bound-bound and bound-unbound Auger processes. Using this method, distributions of carriers involved in bound-bound and bound-unbound recombination processes are carried out. The bound-unbound recombination mechanism is identified as a significant contribution to the Auger total current density. Because the transition matrix element is found to be a significantly increasing function of the quantum-well width, our computations show that the Auger effect is expected to be enhanced in narrow wells. Subsequently, strain dependence of the Auger current density is analyzed. It is found that the Auger effect is reduced by strain in some cases but it is equally shown that this is not a general rule as it depends on the valence subband structure. The effect of temperature on Auger events is also investigated. In particular, it is found, that around room temperature, the temperature sensitivity of Auger current density is quite low in good agreement with many experimental data.