Minority carrier lifetimes and lasing thresholds of PbSnTe heterostructure lasers

A new calculation of radiative minority carrier lifetime in PbSnTe is presented which yields lifetimes an order of magnitude greater than previously accepted values. These results are used in combination with recent measurements of minority carrier lifetime and interface recombination velocity in PbSnTe double heterojunction laser structures to calculate DH laser thresholds. It is demonstrated that radiative recombination is a relatively inefficient process in present PbSnTe lasers, and that when this inefficiency is taken into account the magnitude of the experimentally observed threshold and its variation with active region width and temperature can be accurately predicted, even at low temperatures where all previous models have failed.