Tunable mid-infrared light generation in periodically-poled crystals of the KTiOPO/sub 4/ family and application to gas sensing

Summary form only given. There is a need for sensitive and compact techniques for detection of environmentally important gases and pollutants. Since most of them exhibit their fundamental vibrational transitions in the 2-20 /spl mu/m range, and owing to the fact that the absorption spectrum is unique for each material, mid-infrared optical spectroscopy provides a convenient method for continuous identification and quantitative concentration measurement of gases. Recently, we have constructed a mid-infrared spectrometer based on quasi-phase-matched difference frequency mixing in periodically-poled crystals of the KTiOPO/sub 4/ family (KTP, KTA and RTA).