Auger Recombination in Mid-Infrared Quantum Well Lasers

Abstract

Auger recombination is known to be a significant non-radiative channel in near- and mid-infrared quantum well emitters [1] . As a result, the threshold current density of semiconductor lasers increases substantially with increasing wavelength and temperature, impacting the overall efficiency of a laser-based optoelectronic system. In an Auger process the energy released from an electron-hole recombination is transferred to a third carrier. The one-dimensional confinement of quantum wells and small band offsets (relative to the bandgap) in infrared type-I quantum well geometries permit two fundamentally different categories of Auger mechanisms to operate. We refer to these as activated or thresholdless . In a thresholdless process the absence of an activation energy means that the Auger coefficient of an Auger process varies only weakly with temperature. This contrasts with an activated process where the kinematic threshold causes the Auger coefficient to increase approximately exponentially with temperature. There is no clear consensus in the literature on the nature of Auger recombination in type-I quantum wells, and both have variously been invoked to explain the temperature and wavelength dependence of near- and mid-infrared quantum well lasers [2] , [3] .