Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Spatial multiplexing of soliton microcombs   Dual-comb interferometry utilizes two optical frequency combs to map the
optical field's spectrum to a radio-frequency signal without using moving
parts, allowing improved speed and accuracy. However, the method is compounded
by the complexity and demanding stability associated with operating multiple
laser frequency combs. To overcome these challenges, we demonstrate
simultaneous generation of multiple frequency combs from a single optical
microresonator and a single continuous-wave laser. Similar to space-division
multiplexing, we generate several dissipative Kerr soliton states - circulating
solitonic pulses driven by a continuous-wave laser - in different spatial (or
polarization) modes of a $\mathrm{MgF_2}$ microresonator. Up to three distinct
combs are produced simultaneously, featuring excellent mutual coherence and
substantial repetition rate differences, useful for fast acquisition and
efficient rejection of soliton intermodulation products. Dual-comb spectroscopy
with amplitude and phase retrieval, as well as optical sampling of a breathing
soliton, is realised with the free-running system. Compatibility with
photonic-integrated resonators could enable the deployment of dual- and
triple-comb-based methods to applications where they remained impractical with
current technology.

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The categories of this paper are: hep-th
33
The categories of this paper are: plasm-ph
17
The categories of this paper are: q-fin
10
The categories of this paper are: q-bio
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The categories of this paper are: adap-org
31
The categories of this paper are: ao-sci
30
The categories of this paper are: q-alg
27
The categories of this paper are: comp-gas
0
The categories of this paper are: hep-ph
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The categories of this paper are: econ
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The categories of this paper are: eess
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The categories of this paper are: acc-phys
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The categories of this paper are: chem-ph
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The categories of this paper are: alg-geom
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The categories of this paper are: math-ph
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The categories of this paper are: chao-dyn