Papers by Keyword: Terahertz Laser

Abstract: As we know, quantum cascade lasers (QCLs) are currently the most advanced electrically pumped semiconductor lasers, which emit radiation due to intersubband optical transitions in semiconductor superlattices. Also, quantum cascade laser is one of the best alternatives for reaching the terahertz frequency by semiconductor structures. In this paper, in order to engineer the QCL, effects of Raman inversion as an optical nonlinearity process in active region (QD Hetero structures) of the THz laser has been investigated by using Launda-type three-level system. This would allow suppression of thermally activated optical phonons scattering processes. At the first, the three level QD is designed, where we have considered three Al0.48In0.52As/Ga0.47In0.47As QDs in z direction with the layer sequence of 4/1.5/4/3.5/4 in nanometers. Then, by rate equations in steady-state condition, the laser gain has been calculated.