Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: 1-GHz mid-infrared frequency comb spanning 3 to 13 {\mu}m   Mid-infrared (MIR) spectrometers are invaluable tools for molecular
fingerprinting and hyper-spectral imaging. Among the available spectroscopic
approaches, GHz MIR dual-comb absorption spectrometers have the potential to
simultaneously combine the high-speed, high spectral resolution, and broad
optical bandwidth needed to accurately study complex, transient events in
chemistry, combustion, and microscopy. However, such a spectrometer has not yet
been demonstrated due to the lack of GHz MIR frequency combs with broad and
full spectral coverage. Here, we introduce the first broadband MIR frequency
comb laser platform at 1 GHz repetition rate that achieves spectral coverage
from 3 to 13 {\mu}m. This frequency comb is based on a commercially available
1.56 {\mu}m mode-locked laser, robust all-fiber Er amplifiers and intra-pulse
difference frequency generation (IP-DFG) of few-cycle pulses in \c{hi}(2)
nonlinear crystals. When used in a dual comb spectroscopy (DCS) configuration,
this source will simultaneously enable measurements with {\mu}s time
resolution, 1 GHz (0.03 cm-1) spectral point spacing and a full bandwidth of >5
THz (>166 cm-1) anywhere within the MIR atmospheric windows. This represents a
unique spectroscopic resource for characterizing fast and non-repetitive events
that are currently inaccessible with other sources.

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The categories of this paper are: dg-ga
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The categories of this paper are: alg-geom
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The categories of this paper are: econ
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The categories of this paper are: adap-org
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The categories of this paper are: stat
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The categories of this paper are: q-fin
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The categories of this paper are: plasm-ph
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The categories of this paper are: ao-sci
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The categories of this paper are: cmp-lg
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The categories of this paper are: math
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The categories of this paper are: hep-ph
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The categories of this paper are: math-ph
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The categories of this paper are: q-bio
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The categories of this paper are: supr-con
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The categories of this paper are: bayes-an
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The categories of this paper are: comp-gas