Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Excited-state optically detected magnetic resonance of spin defects in
  hexagonal boron nitride   Negatively charged boron vacancy (VB-) centers in hexagonal boron nitride
(hBN) are promising spin defects in a van der Waals crystal. Understanding the
spin properties of the excited state (ES) is critical for realizing dynamic
nuclear polarization. Here, we report zero-field splitting in the ES of DES =
2160 MHz and an optically detected magnetic resonance (ODMR) contrast of 12% at
cryogenic temperature. The ES has a g-factor similar to the ground state. The
ES photodynamics is further elucidated by measuring the level anti-crossing of
the VB- defects under varying external magnetic fields. In contrast to nitrogen
vacancy (NV-) centers in diamond, the emission change caused by excited-state
level anti-crossing (ESLAC) is more prominent at cryo-temperature than at room
temperature. Our results provide important information for utilizing the spin
defects of hBN in quantum technology.

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The categories of this paper are: astro-ph
35
The categories of this paper are: mtrl-th
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The categories of this paper are: hep-th
2
The categories of this paper are: math
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The categories of this paper are: hep-ex
23
The categories of this paper are: solv-int
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The categories of this paper are: math-ph
20
The categories of this paper are: acc-phys
9
The categories of this paper are: nlin
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The categories of this paper are: q-alg
33
The categories of this paper are: plasm-ph
25
The categories of this paper are: patt-sol
1
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
0
The categories of this paper are: hep-ph