Off-axis QEPAS using a pulsed nanosecond Mid-Infrared Optical Parametric Oscillator

Autor: Lassen, Mikael, Lamard, Laurent, Feng, Yuyang, peremans, Andre, Petersen, Jan C.
Rok vydání: 2016
Předmět:
Zdroj: Opt. Lett. 41, 4118-4121 (2016)
Druh dokumentu: Working Paper
DOI: 10.1364/OL.41.004118
Popis: A trace gas sensor, based on quartz-enhanced photoacoustic spectroscopy (QEPAS), consisting of two acoustically coupled micro-resonators (mR) with an off-axis 20 kHz quartz tuning fork (QTF) is demonstrated. The complete acoustically coupled mR system is optimized based on finite element simulations and experimentally verified. The QEPAS sensor is pumped resonantly by a nanosecond pulsed single-mode mid-infrared optical parametric oscillator (MIR OPO). The sensor is used for spectroscopic measurements on methane in the 3.1 um to 3.5 um wavelength region with a resolution bandwidth of 1 cm^-1 and a detection limit of 0.8 ppm. An Allan deviation analysis shows that the detection limit at optimum integration time for the QEPAS sensor is 32 ppbv@190s and that the background noise is solely due to the thermal noise of the QTF.
Comment: 5 pages, 4 figures, Accepted for publication in optics letters
Databáze: arXiv