Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Output Spectrum of Single-Atom Lasers   We consider a laser composed of a single atom in a microcavity, with a
coherent or incoherent pump. We consider both three- and four-level gain
schemes, and examine the output spectrum of such lasers. We find that the
linewidth generally scales as the inverse of the photon number. For large
atom-field coupling, a vacuum-Rabi doublet structure is obtained. In the
three-level case, this vacuum-Rabi splitting is apparent only for small
intracavity photon numbers, and vanishes for large pumps. In the four-level
scheme, the vacuum-Rabi structure appears at a nonzero pump level, and is
maintained for large pumps, even when the intracavity photon number is larger
than unity. This behavior is explained utilizing the quantum trajectory
approach.

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The categories of this paper are: hep-th
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The categories of this paper are: solv-int
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The categories of this paper are: mtrl-th
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The categories of this paper are: patt-sol
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The categories of this paper are: math
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The categories of this paper are: ao-sci
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The categories of this paper are: bayes-an
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The categories of this paper are: cs
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The categories of this paper are: dg-ga
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The categories of this paper are: physics
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The categories of this paper are: acc-phys
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The categories of this paper are: stat
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The categories of this paper are: hep-lat
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The categories of this paper are: hep-ph
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The categories of this paper are: cond-mat
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The categories of this paper are: nucl-th