We investigate the high temperature performance of conventional separa
te confinement and lattice matched and compressively strained multi-qu
antum-well InGaAsP lasers emitting at 1.3 mum. Low threshold buried he
terostructure lasers operate reproducibly at temperatures as high as 1
30-degrees-C. The rate of threshold change with temperature is describ
ed by T0 approximately 45-degrees-55-degrees for both conventional and
quantum well lasers. The rate of change is not influenced by any modi
fications in the active layer structure. In contrast, excellent correl
ation is observed between the active layer structure, parametrized as
the threshold gain, and the peak cw operating temperature.