Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Phonons in potassium doped graphene: the effects of electron-phonon
  interactions, dimensionality and ad-atom ordering   Graphene phonons are measured as a function of electron doping via the
addition of potassium adatoms. In the low doping regime, the in-plane carbon
G-peak hardens and narrows with increasing doping, analogous to the trend seen
in graphene doped via the field-effect. At high dopings, beyond those
accessible by the field-effect, the G-peak strongly softens and broadens. This
is interpreted as a dynamic, non-adiabatic renormalization of the phonon
self-energy. At dopings between the light and heavily doped regimes, we find a
robust inhomogeneous phase where the potassium coverage is segregated into
regions of high and low density. The phonon energies, linewidths and tunability
are remarkably similar for 1-4 layer graphene, but significantly different to
doped bulk graphite.

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The categories of this paper are: hep-th
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The categories of this paper are: math-ph
18
The categories of this paper are: econ
10
The categories of this paper are: q-bio
30
The categories of this paper are: q-alg
23
The categories of this paper are: solv-int
21
The categories of this paper are: adap-org
17
The categories of this paper are: q-fin
19
The categories of this paper are: eess
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The categories of this paper are: nlin
0
The categories of this paper are: hep-ph
25
The categories of this paper are: patt-sol
36
The categories of this paper are: cmp-lg
1
The categories of this paper are: cs
12
The categories of this paper are: nucl-th
24
The categories of this paper are: dg-ga