Optically pumped type-II interband terahertz lasers

Optically pumped terahertz lasers based on interband transitions in type-II antimonide heterostructures are proposed and modeled in detail. At cryogenic temperatures, the activated nature of the Auger and phonon-assisted mechanisms should provide substantially longer nonradiative lifetimes and higher gains than are attainable with intersubband devices. For emission at lambda=27 mu m, pulsed operation is projected up to 60 K, and > 25 mW of cw output power is calculated for T=30 K. At T=4 K, lasing is expected out to wavelengths as long as 100 mu m. (C) 1999 American Institute of Physics. [S0003-6951(99)04633-1].