Temperature dependence of Auger recombination in a multilayer narrow-band-gap superlattice

Temperature and density-dependent Auger recombination rates are determined for a four-layer broken-gap superlattice designed for suppression of both A uger recombination and intersubband absorption. The structure is intended a s the active region of both optically pumped and diode lasers operating in the midwave infrared. Auger recombination and intersubband absorption are t hought to be among the primary factors contributing to high-threshold curre nt densities in such devices. Ultrafast time-resolved photoluminescence upc onversion was used to measure the Auger rates at lattice temperatures rangi ng from 50 to 300 K. Results are compared to calculated rates using the tem perature-dependent, nonparabolic K.p band structure and momentum-dependent matrix elements. The calculations, which include umklapp processes in the s uperlattice growth direction, are in excellent agreement with the experimen tal results. Comparison of these results with those obtained in other mid-I R semiconductor structures verifies Auger suppression. The measured tempera ture-dependent Auger recombination rates, together with calculations of the gain, provide an upper bound for the characteristic temperature, T-0 = 81 K, for lasers utilizing this superlattice as an active region. [S0163-1829( 98)01043-1].