RT Journal Article T1 A quantum cascade laser-based multi-gas sensor for ambient air monitoring A1 Genner, Andreas A1 Martín Mateos, Pedro A1 Moser, Harald A1 Lendl, Bernhard AB A quantum cascade laser-based sensor for ambient air monitoring is presented and five gases, a ecting the air quality, can be quantified. The light sources are selected to measure CO, NO, NO2, N2O and SO2. The footprint of the measurement setup is designed to fit in two standard 19" rack (48 cm x 65 cm) with 4 height units (18 cm) whereas one is holding the optical components and the other one contains the electronics and data processing unit. The concentrations of the individual analytes are measured using 2f-Wavelength Modulation Spectroscopy (2f-WMS) and a commercially available multipass gas cell defines the optical path. In addition, CO can also be measured with a dispersion-based technique, which allows one to cover a wider concentration range than 2f-WMS. The performance of this prototype has been evaluated in the lab and detection limits in the range of 1ppbv have been achieved. Finally, the applicability of this prototype for ambient air monitoring is shown in a five-week measurement campaign in cooperation with the Municipal Department for Environmental Protection (MA 22) of Vienna, Austria. PB MDPI SN 1424-3210 YR 2020 FD 2020-04-01 LK https://hdl.handle.net/10016/36407 UL https://hdl.handle.net/10016/36407 LA eng NO This article belongs to the Special Issue Mid-Infrared Sensors Based On Semiconductor Lasers and Photonic Integrated Circuits (PICs). NO The authors acknowledge TU Wien Bibliothek for financial support through its Open Access Funding Program. DS e-Archivo RD 18 jul. 2024