Auger recombination dynamics in highly excited HgCdTe

We present quantitative experimental and theoretical results of Auger recombination in highly excited Hg0.795Cd0.205Te. The first direct measurement of carrier density dependence of the recombination processes has been made on a picosecond timescale, with the pump-probe technique using a free-electron laser. Over the excited carrier density range (5 x 10(16) to 3 x 10(17) cm(-3)) and at temperatures from 50 to 295 K studied experimentally, contributions from Auger, Shockley-Read-Hall and radiative recombination mechanisms were calculated. The Auger recombination rates were evaluated using a compact analytic form, with carrier degeneracy included, which has been shown to agree closely with more accurate calculations. Excellent agreement was obtained, with Auger-l dominant at all temperatures, and significantly for T > 225 K when the sample is intrinsic, the Auger-7 contribution was found to be important.