Recombination Luminescence from "Hot" Carriers in Electron-Hole Droplets in Stressed Ge

We have observed luminescence lines from "hot" free excitons and from recombination of "hot" electrons within electron-hole droplets in Ge under uniform $〈111〉$ uniaxial stress. Our results suggest that both "hot" and "cold" electrons coexist in the same electron-hole droplets. We have also measured the total lifetime of the hot electrons, which is in good agreement with intervalley relaxation by electron-electron scattering.