Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Quantum statistics of a single-atom Scovil-Schulz-DuBois heat engine   We study the statistics of the lasing output from a single atom quantum heat
engine, which was originally proposed by Scovil and Schulz-DuBois (SSDB). In
this heat engine model, a single three-level atom is strongly coupled with an
optical cavity, and contacted with a hot and a cold heat bath together. We
derive a fully quantum laser equation for this heat engine model, and obtain
the photon number distribution for both below and above the lasing threshold.
With the increase of the hot bath temperature, the population is inverted and
lasing light comes out. However, we notice that if the hot bath temperature
keeps increasing, the atomic decay rate is also enhanced, which weakens the
lasing gain. As a result, another critical point appears at a very high
temperature of the hot bath, after which the output light become thermal
radiation again. To avoid this double-threshold behavior, we introduce a
four-level heat engine model, where the atomic decay rate does not depend on
the hot bath temperature. In this case, the lasing threshold is much easier to
achieve, and the double-threshold behavior disappears.

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The categories of this paper are: supr-con
29
The categories of this paper are: funct-an
22
The categories of this paper are: chao-dyn
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The categories of this paper are: bayes-an
2
The categories of this paper are: math
14
The categories of this paper are: math-ph
24
The categories of this paper are: dg-ga
3
The categories of this paper are: physics
7
The categories of this paper are: hep-th
9
The categories of this paper are: nlin
17
The categories of this paper are: q-fin
6
The categories of this paper are: astro-ph
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The categories of this paper are: hep-ph
30
The categories of this paper are: q-alg
8
The categories of this paper are: hep-ex
5
The categories of this paper are: gr-qc