Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Single photons by quenching the vacuum   Heisenberg's uncertainty principle implies that the quantum vacuum is not
empty but fluctuates. These fluctuations can be converted into radiation
through nonadiabatic changes in the Hamiltonian. Here, we discuss how to
control this vacuum radiation, engineering a single-photon emitter out of a
two-level system (2LS) ultrastrongly coupled to a finite-band waveguide in a
vacuum state. More precisely, we show the 2LS nonlinearity shapes the vacuum
radiation into a nonGaussian superposition of even and odd cat states. When the
2LS bare frequency lays within the band gaps, this emission can be well
approximated by individual photons. This picture is confirmed by a
characterization of the ground and bound states, and a study of the dynamics
with matrix product states and polaron Hamiltonian methods.

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The categories of this paper are: cond-mat
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The categories of this paper are: ao-sci
21
The categories of this paper are: adap-org
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The categories of this paper are: math
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The categories of this paper are: alg-geom
27
The categories of this paper are: comp-gas
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The categories of this paper are: solv-int
34
The categories of this paper are: chem-ph
25
The categories of this paper are: patt-sol
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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: hep-lat
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The categories of this paper are: math-ph
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The categories of this paper are: hep-th
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The categories of this paper are: funct-an
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The categories of this paper are: gr-qc