The present work reports on the first application of a ring-cavitysurface-emitting quantum-cascade laser (RCSE-QCL) for sensitive gas measurements. RCSE-QCLs are promising candidates for optical gassensing due to their single-mode, mode-hop-free and narrow-band emission characteristics along with their broad spectral coverage. The time resolved down-chirp of the RCSE-QCL in the 1227-1236 cm (8....

A novel design-friendly device called the transistor-injected dual doping quantum cascade laser (TI-D2QCL) with two different in each stack of a homogeneous superlattice is proposed. By adjusting base-emitter bias Vbe bipolar transistor to supply electrons regions, charge quasi-neutrality can be achieved generate optical transitions cascading stack. These are then stacked and amplified contribu...