COCO-QEPAS: fingerprinting a trace gas at ppm-level within seconds (Conference Presentation)

Quartz-enhanced photoacoustic spectroscopy (QEPAS) is a versatile tool for detection of trace gases at extremely low concentrations. However, the identification of unknown trace gases through their full spectral shape has not been addressed yet. Here, we combine QEPAS with a fiber-feedback optical parametric oscillator (FFOPO). The FFOPO allows acquisition of a complete methane spectrum spanning 3050-3450 nm in just three seconds. Our measured data excellently matches the HITRAN database when convolved with the laser linewidth of <2 cm-1. The presented system will enable the use of QEPAS in real-world gas sensing applications beyond laboratory environments with extremely fast capture rate.