Passively Q-switched 214.8-nm Nd:YAG/Cr 4+ :YAG microchip-laser system for the detection of NO

A compact 214.8-nm source, based on the fifth harmonic of a 1.074-μm Nd:YAG/Cr4+:YAG passively Q-switched microchip laser, was developed and used to detect NO at the few-parts-per-billion level.