Year: 2024
Type: editorial
Abstract: Recent advances in cavity-enhanced spectroscopy have led to significant improvements in precision, 18 sensitivity, and range of applications for optical detection and measurement. operating around 1600 nm. One laser is used as probe beam which is injected in a multipass cell and is 27 frequency stabilized against a CO₂ absorption line using frequency modulation spectroscopy, ensuring 28 drift-free laser frequency. 90% of the radiation is injected into a 200-mm-long high-finesse (about 29 45000) cavity, along with the second DFB laser, emitting at a similar wavelength, used to measure 30 absorption-free ring-down time. This stabilization leads to a five-fold improvement in detection 31 sensitivity, reaching 4.410⁻¹¹ cm⁻¹ with a detection limit of 78 ppb, comparable to leading commercial 32 systems. This approach has proven its efficacy in environmental and industrial gas sensing, validating 33 its potential for broad practical applications. 34 CRDS, combined with an optical frequency comb, has been used by Gotti et al.,reaching 35 unprecedented precision in measuring the P(5), P(6), and O(3) transitions of the HD molecule 2-0 band 36 near 1.5 µm. Improving by more than two orders of magnitude the accuracy of the P(5) transition, the 37
Source: Frontiers in Physics
Institutions: University of Insubria, Istituto di Fotonica e Nanotecnologie, Politecnico di Milano, National Oceanic and Atmospheric Administration, Cooperative Institute for Research in Environmental Sciences, University of Colorado Boulder, NOAA Chemical Sciences Laboratory, University of Wisconsin–Madison, University of Pavia
Language: English
Subfield: Spectroscopy
Field: Chemistry
Domain: Physical Sciences
Open Access status: gold
Estimated APC paid: $2,795
OpenAlex ID: W4403405339