Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Tunneling of Obliquely-Incident Waves through PT-Symmetric
  Epsilon-Near-Zero Bi-Layers   We show that obliquely-incident, transversely-magnetic-polarized plane waves
can be totally transmitted (with zero reflection) through epsilon-near-zero
(ENZ) bi-layers characterized by balanced loss and gain with parity-time (PT)
symmetry. This tunneling phenomenon is mediated by the excitation of a
surface-wave localized at the interface separating the loss and gain regions.
We determine the parameter configurations for which the phenomenon may occur
and, in particular, the relationship between the incidence direction and the
electrical thickness. We show that, below a critical threshold of gain and
loss, there always exists a tunneling angle which, for moderately thick
(wavelength-sized) structures, approaches a critical value dictated by the
surface-wave phase-matching condition. We also investigate the unidirectional
character of the tunneling phenomenon, as well as the possible onset of
spontaneous symmetry breaking, typical of PT-symmetric systems. Our results
constitute an interesting example of a PT-symmetry-induced tunneling
phenomenon, and may open up intriguing venues in the applications of ENZ
materials featuring loss and gain.

22
The categories of this paper are: chao-dyn
16
The categories of this paper are: stat
33
The categories of this paper are: plasm-ph
28
The categories of this paper are: alg-geom
7
The categories of this paper are: hep-th
27
The categories of this paper are: comp-gas
23
The categories of this paper are: solv-int
10
The categories of this paper are: q-bio
32
The categories of this paper are: atom-ph
36
The categories of this paper are: cmp-lg
34
The categories of this paper are: chem-ph
25
The categories of this paper are: patt-sol
21
The categories of this paper are: adap-org
35
The categories of this paper are: mtrl-th
19
The categories of this paper are: eess
24
The categories of this paper are: dg-ga