The effect of phonon extraction level separation on the performance of three-well resonant-phonon terahertz quantum-cascade lasers

Abstract

The authors present a simulation and experimental study on the effect of phonon extraction level separation on the performance of GaAs-based three-well resonant-phonon terahertz quantum-cascade lasers (QCLs). The phonon extraction level separation is varied from 30 to 42 meV. Because of the efficient longitudinal-optical phonon scattering, the 36 meV QCL shows the largest gain, the best temperature performance and the highest output power. As for the lower (30 meV) or higher (42 meV) energy separation QCLs, the electron-longitudinal-optical phonon interaction still works by involving a transfer of in-plane momentum. The measured lasing characteristics are in qualitative agreement with simulation.

Effect of injection coupling strength on terahertz quantum-cascade lasers

“…The effects of different design parameters, i.e. injection barrier [14,15] and extraction barrier widths [16], doping [17,18] and phonon extraction level separation [19] on the performance of QCLs have been studied by both experiments and simulations. Furthermore, corresponding optimal values have been found and the simulated results show good agreement with experiments.…”