Auger recombination in long-wavelength infrared InNxSb1-x alloys

Dilute nitrogen alloys of InSb exhibit strong band gap bowing with increasi ng nitrogen composition, shifting the absorption edge to longer wavelengths . The conduction band dispersion also has an enhanced nonparabolicity, whic h suppresses Auger recombination. We have measured Auger lifetimes in alloy s with 11 and 15 mum absorption edges using a time-resolved pump-probe tech nique. We find the lifetimes to be longer at room temperature than equivale nt band gap Hg1-yCdyTe alloys at the same quasi-Fermi level separation. The results are explained using a modified k.p Hamiltonian which explicitly in cludes interactions between the conduction band and a higher lying nitrogen -related resonant band. (C) 2001 American Institute of Physics.