TEMPERATURE-DEPENDENCE OF LIGHT-CURRENT CHARACTERISTICS OF 0.98-MU-M AL-FREE STRAINED-QUANTUM-WELL LASERS

The decrease of the differential efficiency of 0.98-mum semiconductor lasers with temperature can make high power, high temperature applicat ions difficult. We present an experimental and theoretical study of th e temperature dependence of the internal quantum efficiency, internal loss and differential gain of 0.98-mum InGaAs/InGaAsP/InGaP strained q uantum well lasers. In contrast to some earlier results, our measureme nts show the dominance of internal loss, attributed to free carrier ab sorption, in determining the temperature dependence of the differentia l efficiency, and show that leakage current is negligible below 120-de grees-C.