Quantum Cascade Laser Based Chemical Sensing Using Optically Resonant Cavities

Progress in the development of compact semiconductor-based mid-infrared light sources, more specifically of quantum cascade lasers (QCLs), has been astonishingly rapid in the 2 decades since their first realisation. Their performance makes them superior to conventional sources and has led to significant improvements and new developments in chemical sensing techniques encompassing cavity enhanced methods. The aim of this compilation is to provide an overview about useful combinations of QCLs with optical cavities and to highlight recent achievements thereby focussing on potential sensing applications.