Measuring pollutants and outdoor emissions

Detection of molecular gasses at low concentrations is the centrepiece of all applications around laser spectroscopy. It is therefore no surprise that detection of pollutants or other trace gasses in the atmosphere is one of the key applications of these spectroscopic techniques. Using broadband sources, such as frequency combs and/or optical parametric oscillators (OPOs), the broad spectral bandwidth allows simultaneous detection of multiple molecules, which has been demonstrated for methane (CH4) and ethane (C2H6) detection at microsecond time-scales [1]. The use of supercontinuum sources can extend the spectral coverage even further. In recent years, applications have been developed to bring supercontinuum sources to the field in two H2020 programmes, FLAIR and TRIAGE, demonstrating detection of molecules with absorption features between 2 - 10.5 μm, such as CH4, NO, NO2, N2O, C2H6, C2H4, SO2, CO, and CO2 [2,3].

More about this research?

[1] Abbas, M. A. et al. Time-resolved mid-infrared dual-comb spectroscopy. Scientific Reports vol. 9 (2019).
DOI:10.1038/s41598-019-53825-8

[2] Abbas, M. A. et al. Fourier transform spectrometer based on high-repetition-rate mid-infrared supercontinuum sources for trace gas detection. Optics Express vol. 29 22315 (2021).
DOI:10.1364/OE.425995 [Radboud Repository]

[3] Krebbers, R. et al. Mid-infrared supercontinuum-based Fourier transform spectroscopy for plasma analysis. Scientific Reports vol. 12 (2022).
DOI:10.1038/s41598-022-13787-w [Radboud Repository]