Auger lifetime enhancement in InAs–Ga1−xInxSb superlattices

We have experimentally and theoretically investigated the Auger recombination lifetime in InAs–Ga1−xInxSb superlattices. Data were obtained by analyzing the steady-state photoconductive response to frequency-doubled CO2 radiation, at intensities varying by over four orders of magnitude. Theoretical Auger rates were derived, based on a k⋅p calculation of the superlattice band structure in a model which employs no adjustable parameters. At 77 K, both experiment and theory yield Auger lifetimes which are approximately two orders of magnitude longer than those in Hg1−xCdxTe with the same energy gap. This finding has highly favorable implications for the application of InAs–Ga1−xInxSb superlattices to infrared detector and nonlinear optical devices.