Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: A compact, thermal noise limited reference cavity for ultra-low noise
  microwave generation   We demonstrate an easy to manufacture, 25 mm long ultra-stable optical
reference cavity for transportable photonic microwave generation systems.
Employing a rigid holding geometry that is first-order insensitive to the
squeezing force and a cavity geometry that improves the thermal noise limit at
room temperature, we observe a laser phase noise that is nearly thermal noise
limited for three frequency decades (1 Hz to 1 kHz offset) and supports 10 GHz
generation with phase noise near -100 dBc/Hz at 1 Hz offset and <-173 dBc/Hz
for all offsets >600 Hz. The fractional frequency stability reaches
$2\times10^{-15}$ at 0.1 s of averaging.

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The categories of this paper are: hep-ex
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The categories of this paper are: bayes-an
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The categories of this paper are: alg-geom
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The categories of this paper are: hep-th
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The categories of this paper are: adap-org
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The categories of this paper are: chem-ph
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The categories of this paper are: nlin
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The categories of this paper are: acc-phys
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The categories of this paper are: hep-ph
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The categories of this paper are: math
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The categories of this paper are: mtrl-th
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The categories of this paper are: eess
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The categories of this paper are: math-ph
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The categories of this paper are: econ
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The categories of this paper are: q-alg
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The categories of this paper are: solv-int