Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Optimization of the coherence properties of diamond samples with an
  intermediate concentration of NV centers   The sensitivity of the nitrogen-vacancy (NV) color centers in diamond-based
magnetometers strongly depends on the number of NV centers involved in the
measurement. Unfortunately, an increasing concentration of NV centers leads to
decreases of their dephasing and coherence time if the nitrogen content exceeds
a certain threshold level (approximately ${10^{17}}{\rm{ c}}{{\rm{m}}^{ -
3}}$). Here, we demonstrate that this increased dephasing can be efficiently
compensated by postprocessing procedures in the vicinity of the threshold
concertation, thus extending possible useful concentrations on NV centers with
the maximum possible decoherence time in diamonds with a natural carbon
content.

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The categories of this paper are: math
10
The categories of this paper are: q-bio
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The categories of this paper are: q-fin
4
The categories of this paper are: cond-mat
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The categories of this paper are: eess
22
The categories of this paper are: chao-dyn
30
The categories of this paper are: q-alg
5
The categories of this paper are: gr-qc
8
The categories of this paper are: hep-ex
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The categories of this paper are: math-ph
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The categories of this paper are: hep-lat
9
The categories of this paper are: nlin
28
The categories of this paper are: alg-geom
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The categories of this paper are: atom-ph
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The categories of this paper are: solv-int
31
The categories of this paper are: ao-sci