Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Broadband infrared spectroscopy of condensed phases with two intra-pulse
  difference-frequency-generation frequency combs   Mid-infrared (mid-IR) spectroscopy provides a way to study structures and
dynamics of complicated molecules in condensed phases. Therefore, developing
compact and broadband mid-IR spectrometer has been a long-standing challenge.
Here, we show that a highly coherent and broadband mid-IR frequency comb can be
generated by using an intra-pulse difference-frequency-generation with a train
of pulses from a few-cycle Ti:Sapphire oscillator. By tightly focusing the
oscillator output beam into a single-pass fan-out-type periodically-poled
lithium niobate crystal and tilting the orientation of the crystal with respect
to incident beam, it is shown that mid-IR frequency comb with more than an
octave spectral bandwidth from 1550 cm-1 (46 THz) to 3650 cm-1 (110 THz) and
vanishing carrier-envelop offset phase can be generated. Then, using two
coherent mid-IR frequency combs, we demonstrate that ultrabroad mid-IR dual
frequency comb spectroscopy of both aromatic compounds and amino acids in
solutions is experimentally feasible. We thus anticipate that our mid-IR
frequency combs could be used to further develop ultrafast and broadband IR
spectroscopy of chemically reactive and biological molecules in condensed
phases.

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The categories of this paper are: hep-th
32
The categories of this paper are: atom-ph
25
The categories of this paper are: patt-sol
37
The categories of this paper are: supr-con
18
The categories of this paper are: econ
14
The categories of this paper are: math-ph
1
The categories of this paper are: cs
2
The categories of this paper are: math
20
The categories of this paper are: acc-phys
15
The categories of this paper are: nucl-ex
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The categories of this paper are: eess
17
The categories of this paper are: q-fin
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The categories of this paper are: quant-ph
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The categories of this paper are: mtrl-th
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The categories of this paper are: adap-org
28
The categories of this paper are: alg-geom