Abstract

III-nitrides which have much larger phonon energies (91meV in GaN) can in principle allow for terahertz quantum cascade lasers (THz QCLs) to operate at higher temperatures than GaAs based THz QCLs[1-2], in which the thermally activated phonon scattering depopulation and backfilling are limiting THz lasing at <200 K. GaN THz-QCLs would be key coherent sources in the unexplored terahertz frequency range of 5-12 THz, at which GaAs THz-QCLs are not able to work due to the Reststrahlen band.

© 2017 Japan Society of Applied Physics, Optical Society of America