Quasi-continuous-wave operation of AlGaAs/GaAs quantum cascade lasers

Quasi-continuous-wave operation of AlGaAs/GaAs-based quantum cascade lasers (λ∼9 μm) up to 165 K is reported. The strong temperature dependence of the threshold current density and its higher value in high duty cycle is investigated in detail. The self-heating effect in the active region is explored by changing the operating duty cycles. The degradation of lasing performance with temperature is explained.