Potential-inserted quantum well design for quantum cascade terahertz lasers

Design Optimization for 4.1-THZ Quantum Cascade Lasers

We present an optimized design for GaAs/AlGaAs quantum cascade lasers operating at ‎‎4.1THz. This was based on a three-well active module with diagonal radiative transition. This ‎was performed by modifying the existing model structure, to reduce the parasitic anticrossings ‎‎(leakage currents) as well as the optical gain linewidth. While the gain FWHM was reduced by ‎more than 50% the gain pea...

Nanowire terahertz quantum cascade lasers

Terahertz quantum cascade lasers based on intra-well optical transitions

The possibility to achieve laser action at different THz frequencies employing the so-called vertical transition will be discussed. The intra-well or vertical optical transition presents a number of features that makes it an ideal candidate for a systematic study of resonant tunnelling and dephasing in quantum cascade lasers. Laser action at 3.5 THz with very low threshold employing a single qu...

Two-well terahertz quantum cascade lasers with suppressed carrier leakage

Temperature Effect on THz Quantum Cascade Lasers

A simple semi-phenomenological model, which accurately predicts the dependence of thresholdcurrent for temperature of Resonant-phonon three well quantum cascade laser based on verticaltransitions is offered. We found that, the longitude optical phonon scattering of thermally excitedelectrons is the most important limiting factor for thermal performance of high frequency THz QCLs.In low frequenc...