Low current-density THz quantum-cascade lasers with three-well period, epitaxially grown with As2 and As4 sources

Abstract

We report terahertz (THz) quantum-cascade lasers (QCLs) based on a three-well GaAs/AlGaAs active region with resonant-phonon depopulation that achieve high operating temperatures at low current densities. An investigation of THz QCLs epitaxially grown with dimer (As2) and tetramer (As4) arsenic species was also performed. Maximum pulsed operating temperature of 163 K at a peak current density of 513 A/cm2 is reported for a 3 THz QCL grown with As4. Alternately, a 3 THz QCL grown with As2 operated up to 153 K at a peak current density of 367 A/cm2. Continuous-wave operation up to 109 K is also realized for a 60 μm wide Fabry–Pérot cavity laser.