Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Observation of intensity squeezing in resonance fluorescence from a
  solid-state device   Intensity squeezing, i.e., photon number fluctuations below the shot noise
limit, is a fundamental aspect of quantum optics and has wide applications in
quantum metrology. It was predicted in 1979 that the intensity squeezing could
be observed in resonance fluorescence from a two-level quantum system. Yet, its
experimental observation in solid states was hindered by inefficiencies in
generating, collecting and detecting resonance fluorescence. Here, we report
the intensity squeezing in a single-mode fibre-coupled resonance fluorescence
single-photon source based on a quantum dot-micropillar system. We detect
pulsed single-photon streams with 22.6% system efficiency, which show
subshot-noise intensity fluctuation with an intensity squeezing of 0.59 dB. We
estimate a corrected squeezing of 3.29 dB at the first lens. The observed
intensity squeezing provides the last piece of the fundamental picture of
resonance fluorescence; which can be used as a new standard for optical
radiation and in scalable quantum metrology with indistinguishable single
photons.

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The categories of this paper are: math
7
The categories of this paper are: hep-th
22
The categories of this paper are: chao-dyn
32
The categories of this paper are: atom-ph
15
The categories of this paper are: nucl-ex
25
The categories of this paper are: patt-sol
35
The categories of this paper are: mtrl-th
20
The categories of this paper are: acc-phys
14
The categories of this paper are: math-ph
10
The categories of this paper are: q-bio
29
The categories of this paper are: funct-an
11
The categories of this paper are: hep-lat
34
The categories of this paper are: chem-ph
24
The categories of this paper are: dg-ga
16
The categories of this paper are: stat
26
The categories of this paper are: bayes-an