Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Photo-acoustic dual-frequency comb spectroscopy   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.

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The categories of this paper are: quant-ph
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The categories of this paper are: stat
18
The categories of this paper are: econ
37
The categories of this paper are: supr-con
32
The categories of this paper are: atom-ph
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The categories of this paper are: solv-int
35
The categories of this paper are: mtrl-th
1
The categories of this paper are: cs
25
The categories of this paper are: patt-sol
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The categories of this paper are: eess
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The categories of this paper are: alg-geom
34
The categories of this paper are: chem-ph
30
The categories of this paper are: q-alg
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The categories of this paper are: nucl-ex
31
The categories of this paper are: ao-sci
0
The categories of this paper are: hep-ph