2.7-μm InGaAsSb/AlGaAsSb laser diodes with continuous wave operation up to -39°c

Continuous and quasi-continuous wave operation of 2.7-μ InGaAsSb/AlGaAsSb multi-quantum-well (MQW) lasers was demonstrated up to a temperature of 234 K (-39°C) and 253 K (-20°C), respectively. These devices were grown by molecular-beam epitaxy (MBE). They tend to operate in a dominant single mode over well defined temperature and current intervals. A comparison of spontaneous emission spectra shows that above threshold the quasi-Fermi level is pinned and that most of the carriers are injected into non-lasing states. This effect leads to a rapid decrease of differential efficiency with increasing temperature.