High-power terahertz quantum-cascade lasers

Demonstration of quantum-cascade lasers at similar to 4.4 THz (lambda similar to 68 mu m), which are measured to emit 248 mW peak power in pulsed mode, and 138 mW continuous-wave power at heatsink temperatures of 10 K, is reported. These lasers are based on a resonant-phonon depopulation scheme, and use a semi-insulating surface-plasmon waveguide.