Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Local and bulk 13C hyperpolarization in NV-centered diamonds at variable
  fields and orientations   Polarizing nuclear spins is of fundamental importance in biology, chemistry
and physics. Methods for hyperpolarizing 13C nuclei from free electrons in
bulk, usually demand operation at cryogenic temperatures. Room-temperature
approaches targeting diamonds with nitrogen-vacancy (NV) centers could
alleviate this need, but hitherto proposed strategies lack generality as they
demand stringent conditions on the strength and/or alignment of the magnetic
field. We report here an approach for achieving efficient electron->13C spin
alignment transfers, compatible with a broad range of magnetic field strengths
and field orientations with respect to the diamond crystal. This versatility
results from combining coherent microwave- and incoherent laser-induced
transitions between selected energy states of the coupled electron-nuclear spin
manifold. 13C-detected Nuclear Magnetic Resonance (NMR) experiments demonstrate
that this hyperpolarization can be transferred via first-shell or via distant
13Cs, throughout the nuclear bulk ensemble. This method opens new perspectives
for applications of diamond NV centers in NMR, and in quantum information
processing.

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The categories of this paper are: q-alg
6
The categories of this paper are: astro-ph
18
The categories of this paper are: econ
37
The categories of this paper are: supr-con
20
The categories of this paper are: acc-phys
31
The categories of this paper are: ao-sci
9
The categories of this paper are: nlin
35
The categories of this paper are: mtrl-th
8
The categories of this paper are: hep-ex
29
The categories of this paper are: funct-an
22
The categories of this paper are: chao-dyn
0
The categories of this paper are: hep-ph
14
The categories of this paper are: math-ph
36
The categories of this paper are: cmp-lg
17
The categories of this paper are: q-fin
19
The categories of this paper are: eess