Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Theory of the electronic and transport properties of graphene under a
  periodic electric or magnetic field   We discuss the novel electronic properties of graphene under an external
periodic scalar or vector potential, and the analytical and numerical methods
used to investigate them. When graphene is subjected to a one-dimensional
periodic scalar potential, owing to the linear dispersion and the chiral
(pseudospin) nature of the electronic states, the group velocity of its
carriers is renormalized highly anisotropically in such a manner that the
velocity is invariant along the periodic direction but is reduced the most
along the perpendicular direction. Under a periodic scalar potential, new
massless Dirac fermions are generated at the supercell Brillouin zone
boundaries. Also, we show that if the strength of the applied scalar potential
is sufficiently strong, new zero-energy modes may be generated. With the
periodic scalar potential satisfying some special conditions, the energy
dispersion near the Dirac point becomes quasi one-dimensional. On the other
hand, for graphene under a one-dimensional periodic vector potential (resulting
in a periodic magnetic field perpendicular to the graphene plane), the group
velocity is reduced isotropically and monotonically with the strength of the
potential.

9
The categories of this paper are: nlin
11
The categories of this paper are: hep-lat
33
The categories of this paper are: plasm-ph
36
The categories of this paper are: cmp-lg
23
The categories of this paper are: solv-int
12
The categories of this paper are: nucl-th
14
The categories of this paper are: math-ph
21
The categories of this paper are: adap-org
2
The categories of this paper are: math
18
The categories of this paper are: econ
5
The categories of this paper are: gr-qc
28
The categories of this paper are: alg-geom
13
The categories of this paper are: quant-ph
29
The categories of this paper are: funct-an
20
The categories of this paper are: acc-phys
0
The categories of this paper are: hep-ph