Auger recombination dynamics of InxGa1-xSb

The alloy In1-xGaxSb has been identified as potentially an important compon ent in mid-infrared laser diodes which use band structure engineering of qu antum structures based on the narrow-gap III-V material InSb. A pump-probe measurement has been made of carrier recombination in bulk In1-xGaxSb, far a range of alloy compositions. Over the range of excited carrier densities (5 x 10(16)-3 x 10(17) cm(-3)) and at the temperatures (30-300 K) studied e xperimentally, contributions to the recombination from Auger, Shockley-Read -Hall and radiative mechanisms were calculated using an analytic approximat ion, with carrier degeneracy included. Excellent agreement with experiment was obtained over the alloy range x = 0.0-0.2 (corresponding to a room-temp erature energy gap variation from 0.175 eV to 0.215 eV). Numerically the ro om-temperature Auger coefficient, C, decreased from the value 1.17 x 10(26) cm(6) s(-1) at x = 0 (i.e. InSb) to 0.98 x 10(26) cm(6) s(-1) at x = 0.2. The fact that C decreases with energy gap increase, in good agreement with theoretical predictions, is important for strained layer quantum well devic e applications.