Hot electron relaxation in In0.53Ga0.47As

We have determined the hot carrier energy loss rate to the lattice by measuring the cooling curve of a photoexcited hot plasma in In_0.53Ga_0.47As. These measurements were made by using a sensitive upconversion technique to measure the infrared (1.2−1.6 μm) luminescence with 10 ps time resolution. We find the carrier energy loss rate to be about an order of magnitude smaller than predicted by a simple model, and surprisingly insensitive to carrier density at high densities.