Mesa-stripe Pb1-xSnxSe tunable diode lasers

A mesa-stripe configuration for diffused junction Pb1-xSnx- Se lasers has been developed. The new lasers exhibit substantially improved performance over nonstripe devices, including CW operating temperatures up to 118 K, overall tuning ranges as wide as 444 cm-1, and single-mode tuning ranges typically 1-3 cm-1for current tuning and as wide as 5.5 cm-1for temperature tuning. Surface leakage currents are shown to have a major effect on the operating characteristics of these and other Pb-salt devices. Results provide evidence for high internal quantum efficiencies and indicate that free carrier absorption is an important factor limiting power output in Pb-salt lasers. Observations of spectral mode behavior as a function of bias current are consistent with Zee's gain saturation model.