Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Unique optical characteristics of a Fabry-Perot resonator with embedded
  PT-symmetrical grating   We explore the optical properties of a Fabry-Perot resonator with an embedded
Parity-Time (PT) symmetrical grating. This PT-symmetrical grating is non
diffractive (transparent) when illuminated from one side and diffracting (Bragg
reflection) when illuminated from the other side, thus providing a
unidirectional reflective functionality. The incorporated PT-symmetrical
grating forms a resonator with two embedded cavities. We analyze the
transmission and reflection properties of these new structures through a
transfer matrix approach. Depending on the resonator geometry these cavities
can interact with different degrees of coherency: fully constructive
interaction, partially constructive interaction, partially destructive
interaction, and finally their interaction can be completely destructive. A
number of very unusual (exotic) nonsymmetrical absorption and amplification
behaviors are observed. The proposed structure also exhibits unusual lasing
performance. Due to the PT-symmetrical grating, there is no chance of mode
hopping; it can lase with only a single longitudinal mode for any distance
between the distributed reflectors.

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The categories of this paper are: plasm-ph
2
The categories of this paper are: math
22
The categories of this paper are: chao-dyn
18
The categories of this paper are: econ
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The categories of this paper are: acc-phys
1
The categories of this paper are: cs
15
The categories of this paper are: nucl-ex
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The categories of this paper are: adap-org
10
The categories of this paper are: q-bio
12
The categories of this paper are: nucl-th
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The categories of this paper are: q-alg
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The categories of this paper are: funct-an
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The categories of this paper are: patt-sol
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The categories of this paper are: stat
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The categories of this paper are: astro-ph
31
The categories of this paper are: ao-sci