Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Velocity renormalization and Dirac cone multiplication in graphene
  superlattices with various barrier edge geometries   The electronic properties of one-dimensional graphene superlattices strongly
depend on the atomic size and orientation of the 1D external periodic
potential. Using a tight-binding approach, we show that the armchair and zigzag
directions in these superlattices have a different impact on the
renormalization of the anisotropic velocity of the charge carriers. For
symmetric potential barriers, the velocity perpendicular to the barrier is
modified for the armchair direction while remaining unchanged in the zigzag
case. For asymmetric barriers, the initial symmetry between the forward and
backward momentum with respect to the Dirac cone symmetry is broken for the
velocity perpendicular (armchair case) or parallel (zigzag case) to the
barriers. At last, Dirac cone multiplication at the charge neutrality point
occurs only for the zigzag geometry. In contrast, band gaps appear in the
electronic structure of the graphene superlattice with barrier in the armchair
direction.

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The categories of this paper are: nucl-th
31
The categories of this paper are: ao-sci
36
The categories of this paper are: cmp-lg
32
The categories of this paper are: atom-ph
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The categories of this paper are: hep-lat
0
The categories of this paper are: hep-ph
6
The categories of this paper are: astro-ph
1
The categories of this paper are: cs
35
The categories of this paper are: mtrl-th
24
The categories of this paper are: dg-ga
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The categories of this paper are: quant-ph
30
The categories of this paper are: q-alg
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The categories of this paper are: math-ph
33
The categories of this paper are: plasm-ph
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The categories of this paper are: alg-geom
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The categories of this paper are: adap-org