Sub-ppb detection of benzene using cantilever-enhanced photoacoustic spectroscopy with a long-wavelength infrared quantum cascade laser

Juho Karhu (1) , Hadrien Philip (2) , Alexei Baranov (2, 3) , Roland Teissier (2, 3) , Tuomas Hieta

1 Helsingin yliopisto = Helsingfors universitet = University of Helsinki
2 IES - Institut d’Electronique et des Systèmes
3 NANOMIR - Composants à Nanostructure pour le moyen infrarouge

We report a novel photoacoustic spectrometer for trace gas sensing of benzene. A quantum cascade laser emitting at the wavelength 14.8 µm is used as the light source in the spectroscopic detection. This wavelength region contains the strongest vibrational band of ben-zene, which is free of spectral overlap from common trace gases, making it a strong candidate for sensitive benzene detection. Cantilever-enhanced photoacoustic spectroscopy is used for detection. This simple and robust measurement setup can reach a benzene detection limit below 1 ppb.

Domaines: Ingénierie de l'environnement

Juho Karhu, Hadrien Philip, Alexei Baranov, Roland Teissier, Tuomas Hieta. Sub-ppb detection of benzene using cantilever-enhanced photoacoustic spectroscopy with a long-wavelength infrared quantum cascade laser. Optics Letters, 2020, 45 (21), pp.5962. ⟨10.1364/OL.405402⟩. ⟨hal-03015126⟩