III-V interband 5.2 μm laser operating at 185 K

We report the operation of a III-V interband laser at a wavelength beyond 5 mu m and temperatures above 90 K. The active region consists of a strain compensated broken gap four layer superlattice of InAs/Ga0.6In0.4Sb/InAs/Al0.3Ga0.42In0.28As0.5Sb0.5 grown by molecular beam epitaxy. The maximum operating temperature under 2.01 mu m pulsed optical excitation was 185 K at a wavelength of 5.2 mu m, The peak pump intensity at the 80 K threshold was 62 kW/cm(2), and the characteristic temperature (T-0) of the threshold intensity was 37 K. This T-0 is comparable to the best observed values for 3-4.5 mu m lasers based on the InAs/GaInSb material system. (C) 1997 American Institute of Physics. [S0003-6951(97)04252-6].