Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Plasmonic Dirac Cone in Twisted Bilayer Graphene   We discuss plasmons of biased twisted bilayer graphene when the Fermi level
lies inside the gap. The collective excitations are a network of chiral edge
plasmons (CEP) entirely composed of excitations in the topological electronic
edge states (EES) that appear at the AB-BA interfaces. The CEP form an
hexagonal network with an unique energy scale
$\epsilon_p=\frac{e^2}{\epsilon_0\epsilon t_0}$ with $t_0$ the moir\'e lattice
constant and $\epsilon$ the dielectric constant. From the dielectric matrix we
obtain the plasmon spectra that has two main characteristics: (i) a diverging
density of states at zero energy, and (ii) the presence of a plasmonic Dirac
cone at $\hbar\omega\sim\epsilon_p/2$ with sound velocity $v_D=0.0075c$, which
is formed by zigzag and armchair current oscillations. A network model reveals
that the antisymmetry of the plasmon bands implies that CEP scatter at the
hexagon vertices maximally in the deflected chiral outgoing directions, with a
current ratio of 4/9 into each of the deflected directions and 1/9 into the
forward one. We show that scanning near-field microscopy should be able to
observe the predicted plasmonic Dirac cone and its broken symmetry phases.

28
The categories of this paper are: alg-geom
5
The categories of this paper are: gr-qc
30
The categories of this paper are: q-alg
7
The categories of this paper are: hep-th
13
The categories of this paper are: quant-ph
9
The categories of this paper are: nlin
33
The categories of this paper are: plasm-ph
15
The categories of this paper are: nucl-ex
8
The categories of this paper are: hep-ex
1
The categories of this paper are: cs
24
The categories of this paper are: dg-ga
2
The categories of this paper are: math
27
The categories of this paper are: comp-gas
18
The categories of this paper are: econ
34
The categories of this paper are: chem-ph
0
The categories of this paper are: hep-ph