Distributed feedback quantum cascade lasers

Pulsed single mode operation of distributed feedback quantum cascade lasers is reported above room temperature at both 5.4 and 8 μm wavelengths. Peak optical powers up to 60 mW at 300 K are obtained with a tuning range of ∼60 nm from 100 to ∼320 K. The linewidth is limited by thermal drift during the pulse with a typical value of 0.3 ${\mathrm{cm}}^{\mathrm{-1}}$ for a 10 ns long pulse at 300 K.