Mid-infrared spectral “fingerprints” of many hazardous and harmful gaseous substances are characterized by broad absorption bands, resulting from the merging of several absorption lines corresponding to ro-vibrational transitions. Broadband absorption spectroscopy is fundamental to detect and discriminate these substances. Here we report on a quartz-enhanced photoacoustic spectroscopy sensor for broadband absorbers detection, employing a monolithic array of 32, individually addressable, distributed-feedback quantum cascade lasers as the excitation source. This light source combines a fast tuning speed with a large tuning range, from 1190 cm−1 to 1340 cm−1 together with a high stability. The QEPAS sensor was tested for nitrous oxide (N2O) and methane (CH4) detection, exhibiting absorption features in the laser source emission spectral range. The two broad P- and R- absorption branches of N2O have been accurately reconstructed, as well as several absorption features of CH4, for gas concentrations ranging from 200 to 1000 part-per-million in nitrogen.
Broadband Gas QEPAS Detection Exploiting a Monolithic DFB-QCL Array / Giglio, Marilena; Zifarelli, Andrea; Patimisco, Pietro; Sampaolo, Angelo; Menduni, Giansergio; Elefante, Arianna; Blanchard, Romain; Pfluegl, Christian; Witinski, Mark F.; Vakhshoori, Daryoosh; Tittel, Frank K.; Spagnolo, Vincenzo (NATO SCIENCE FOR PEACE AND SECURITY SERIES. B, PHYSICS AND BIOPHYSICS). - In: Terahertz (THz), Mid Infrared (MIR) and Near Infrared (NIR) Technologies for Protection of Critical Infrastructures Against Explosives and CBRN / [a cura di] Mauro Fernandes Pereira ;Apostolos Apostolakis. - STAMPA. - Dordrecht : Springer Nature, 2021. - ISBN 978-94-024-2081-4. - pp. 61-70 [10.1007/978-94-024-2082-1_5]
Broadband Gas QEPAS Detection Exploiting a Monolithic DFB-QCL Array
Marilena Giglio
;Pietro Patimisco;Angelo Sampaolo;Giansergio Menduni;Vincenzo Spagnolo
2021-01-01
Abstract
Mid-infrared spectral “fingerprints” of many hazardous and harmful gaseous substances are characterized by broad absorption bands, resulting from the merging of several absorption lines corresponding to ro-vibrational transitions. Broadband absorption spectroscopy is fundamental to detect and discriminate these substances. Here we report on a quartz-enhanced photoacoustic spectroscopy sensor for broadband absorbers detection, employing a monolithic array of 32, individually addressable, distributed-feedback quantum cascade lasers as the excitation source. This light source combines a fast tuning speed with a large tuning range, from 1190 cm−1 to 1340 cm−1 together with a high stability. The QEPAS sensor was tested for nitrous oxide (N2O) and methane (CH4) detection, exhibiting absorption features in the laser source emission spectral range. The two broad P- and R- absorption branches of N2O have been accurately reconstructed, as well as several absorption features of CH4, for gas concentrations ranging from 200 to 1000 part-per-million in nitrogen.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
