Far-infrared (λ ≃ 87 μm) bound-to-continuum quantum-cascade lasers operating up to 90 K

We report terahertz frequency (3.5 THz, lambda similar or equal to 87 mum) emission from quantum-cascade lasers employing a bound-to-continuum transition in the active region. The maximum operating temperature is in excess of 90 K. Peak powers of 20 mW at 20 K and 10 mW at 77 K are achieved. The same devices show continuous-wave operation up to 55 K with measured optical powers of 15 mW at 10 K. (C) 2003 American Institute of Physics.