Photo-acoustic dual-frequency comb spectroscopy
Abstract
Photo-acoustic spectroscopy (PAS) is one of the most sensitive non-destructive analysis techniques for gases, fluids and solids. It can operate background-free at any wavelength and is applicable to microscopic and even non-transparent samples. Extension of PAS to broadband wavelength coverage is a powerful tool, though challenging to implement without sacrifice of wavelength resolution and acquisition speed. Here, we show that the unmatched precision, speed and wavelength coverage of dual-frequency comb spectroscopy (DCS) can be combined with the advantages of photo-acoustic detection. Acoustic wave interferograms are generated in the sample by dual-comb absorption and detected by a microphone. As an example, weak gas absorption features are precisely and rapidly sampled; long-term coherent averaging further increases the sensitivity. This novel approach of photo-acoustic dual-frequency comb spectroscopy generates unprecedented opportunities for rapid and sensitive multi-species molecular analysis across all wavelengths of light.
Cite
@article{arxiv.2004.04691,
title = {Photo-acoustic dual-frequency comb spectroscopy},
author = {Thibault Wildi and Thibault Voumard and Victor Brasch and Gürkan Yilmaz and Tobias Herr},
journal= {arXiv preprint arXiv:2004.04691},
year = {2024}
}