Recent advances in quantum cascade lasers

Quantum cascade (QC) lasers are fundamentally new semiconductor lasers based on intersubband transitions and on electrons emitting one photon per stage as they cascade through a periodic quantum well structure. As such their wavelength can be tailored over a wide range and their differential efficiency is inherently greater than unity leading to high power operation. Recent results will be presented demonstrating high power room temperature pulsed operation from 5 to 11.6 μm, with peak powers ranging from 200 to 50 mW