Abstract
Quantum cascade lasers emitting below 3 μm are demonstrated. The lasers based on the InAs/AlSb material system emit at 2.95-2.97 μm in pulsed mode with threshold current densities near 3 kA/cm2 at 84 K and operate up to room temperature. No degradation has been observed in laser performances compared with InAs/AlSb quantum cascade lasers emitting at 3.14-3.35 μm. The obtained results show no influence of the L valley in InAs on operation of these short wavelength quantum cascade lasers