The Growth, Steady State and Decay of the Photocarrier Population at low Temperatures

Abstract

ABSTRACTWe used the transient infrared photoconductivity to measure the rise and fall of the non-equilibrium photocarrier concentration n at helium temperatures and the conditions for recombination. The growth rate of n was found to be only a few percent of the electron-hole pair generation rate G in agreement with LESR data of Street and Biegelsen. The saturation value of n is about 1017cm−3 and nearly independent of G. After turning off the generation light, the residual n requires an hour to decrease by a factor 2 but it can be made to recombine in seconds by infrared light.