Hydrostatic pressure dependence of the threshold current in 1.5 mu m strained quantum well lasers

Results are presented which show that the radiative current in 1.5 mu m quantum well lasers obeys simple theory but that the total current through the device at room temperature is dominated by Auger recombination. The measured temperature and pressure dependencies of the threshold current show that it is phonon-assisted Auger recombination that is operative. This is less sensitive than band-to-band Auger processes to the exact form of the band structure and explains why inbuilt strain has little effect on the temperature sensitivity of the threshold current and why there is little change in threshold current as one goes from 1.5 to 1.3 mu m devices.