Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Unidirectional Invisibility and PT-Symmetry with Graphene   We investigate the reflectionlessness and invisibility properties in the
transverse electric (TE) mode solution of a linear homogeneous optical system
which comprises the $\mathcal{PT}$-symmetric structures covered by graphene
sheets. We derive analytic expressions, indicate roles of each parameter
governing optical system with graphene and justify that optimal conditions of
these parameters give rise to broadband and wide angle invisibility. Presence
of graphene turns out to shift the invisible wavelength range and to reduce the
required gain amount considerably, based on its chemical potential and
temperature. We substantiate that our results yield broadband reflectionless
and invisible configurations for realistic materials of small refractive
indices, usually around $\eta = 1$, and of small thickness sizes with graphene
sheets of rather small temperatures and chemical potentials. Finally, we
demonstrate that pure $\mathcal{PT}$-symmetric graphene yields invisibility at
small temperatures and chemical potentials.

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The categories of this paper are: atom-ph
5
The categories of this paper are: gr-qc
8
The categories of this paper are: hep-ex
7
The categories of this paper are: hep-th
6
The categories of this paper are: astro-ph
34
The categories of this paper are: chem-ph
0
The categories of this paper are: hep-ph
20
The categories of this paper are: acc-phys
22
The categories of this paper are: chao-dyn
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The categories of this paper are: mtrl-th
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The categories of this paper are: dg-ga
21
The categories of this paper are: adap-org
19
The categories of this paper are: eess
18
The categories of this paper are: econ
9
The categories of this paper are: nlin
31
The categories of this paper are: ao-sci