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arXiv · 2312.07038

Broadband near-ultraviolet dual comb spectroscopy

Lukas Fuerst·Adrian Kirchner·Alexander Eber·Florian Siegrist·Robert di Vora·Birgitta Bernhardt
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Abstract

The highly energetic photons of ultraviolet light drive electronic and rovibronic transitions in all molecular species. This radiation is thus a prime tool for strongly selective spectroscopic fingerprinting and real-time environmental monitoring if broad spectral coverage, short acquisition times and high spectral resolution is achieved - requirements that are in mutual competition in traditional applications. As a novel approach with intrinsic potency in all three aspects, here we introduce ultraviolet dual comb spectroscopy using two broadband ultraviolet frequency combs centered at 871 THz and covering a spectral bandwidth of 35.7 THz. Within a 100 us acquisition time window, we obtain rotational state-resolved absorption spectra of formaldehyde, a prototype molecule with high relevance for laser spectroscopy and environmental sciences. This is the first realization of broadband dual comb spectroscopy in the ultraviolet spectral region and a pioneering tool to allow for real-time monitoring of rovibronic transitions.

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Lukas Fuerst, Adrian Kirchner, Alexander Eber, Florian Siegrist, Robert di Vora, Birgitta Bernhardt. 2023-12-12. Broadband near-ultraviolet dual comb spectroscopy. https://doi.org/10.21203/rs.3.rs-2760097%2Fv1

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