Quantum-cascade-laser- (QCL) pumped molecular lasers (QPMLs) have recently been introduced as a source of powerful ($>\phantom{\rule{-2pt}{0ex}}1$ mW) tunable THz) narrow-band ($<\phantom{\rule{-2pt}{0ex}}10$ kHz) continuous-wave terahertz radiation. The performance these depends critically on collision physics, pump saturation, and the design laser cavity. Using validated three-level mod...

Continuous wave operation of quantum cascade lasers is reported up to a temperature of 312 kelvin. The devices were fabricated as buried heterostructure lasers with high-reflection coatings on both laser facets, resulting in continuous wave operation with optical output power ranging from 17 milliwatts at 292 kelvin to 3 milliwatts at 312 kelvin, at an emission wavelength of 9.1 micrometers. Th...