Temperature dependence of light-current characteristics of0.98-μm Al-free strained-quantum-well lasers

The decrease of the differential efficiency of 0.98-μm semiconductor lasers with temperature can make high power, high temperature applications difficult. We present an experimental and theoretical study of the temperature dependence of the internal quantum efficiency, internal loss and differential gain of 0.98-μm InGaAs/InGaAsP/InGaP strained quantum well lasers. In contrast to some earlier results, our measurements show the dominance of internal loss, attributed to free carrier absorption, in determining the temperature dependence of the differential efficiency, and show that leakage current is negligible below 120°C