Quartz-enhanced photoacoustic sensor for ethylene detection implementing optimized custom tuning fork-based spectrophone

• DOI: 10.1364/oe.27.004271
• Publication Date: 2019-02-06T15:45:19Z
• Authors: Marilena Giglio; Arianna Elefante; Pietro Patimisco; Angelo Sampaolo; Fabrizio Sgobba; Hubert Rossmadl; Verena Mackowiak; Hongpeng Wu; Frank K. Tittel; Lei Dong; Vincenzo Spagnolo
• Keywords: Photoacoustic Spectroscopy; SIGNAL (programming language); Realization (probability); Linear range

The design and realization of two highly sensitive easily interchangeable spectrophones based on custom quartz tuning forks, with a rectangular (S1) or T-shaped (S2) prongs geometry, is reported. have been implemented in QEPAS sensor for ethylene detection, employing DFB-QCL emitting at 10.337 μm an optical power 74.2 mW. A comparison between their performances showed signal-to-noise ratio 3.4 times higher when implementing the S2 spectrophone. For S2-based sensor, linear dependence signal concentration was demonstrated 5 ppm -100 range. 10 s lock-in integration time, minimum detection limit ppb calculated.