Numerical simulation of GaAs-based mid-infrared one-phonon resonance quantum cascade laser

Non-equilibrium Green’s function method is used to analyze electronic transport in a mid-infrared quantum cascade laser on microscopic level. Basing on the excellent agreement found between calculated and experimental data, the conclusions are derived that the carrier distribution in the lower laser subband is non-thermal, and the carriers are extracted from active region both in cold and hot state. An estimate τ 3 = 0.66 ps for upper lifetime at 77 K was found which considerably differs from the value 1.4 ps evaluated from the form factors.