Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Exotic light dynamics around a fourth order exceptional point   The physics of exceptional point (EP) singularities, has been a key to a wide
range of unique physical applications in open systems. In this context, the
mutual interactions among four coupled states around a fourth-order EP (EP4) in
a physical system is yet to be explored. Here, we investigate the unique
features of an EP4 in a fabrication feasible planar optical waveguide with a
multilayer gain-loss profile based on only two tunable parameters. A unique
`fourth-order $\beta$-switching' phenomenon due to quasi-static gain-loss
variation around EP4 has been explored. An exclusive chiral light dynamics
following the dynamical variation of the gain-loss profile has been reported
for the first time, which enables a special type of asymmetric higher-order
mode conversion scheme. Here, all the coupled modes associated with an EP4 are
fully converted into different specific higher-order modes based on the choice
of encirclement directions. The proposed scheme would present EP4 as a new
light manipulation tool for integrated photonic devices.

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The categories of this paper are: gr-qc
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The categories of this paper are: chem-ph
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The categories of this paper are: nlin
19
The categories of this paper are: eess
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The categories of this paper are: quant-ph
12
The categories of this paper are: nucl-th
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The categories of this paper are: patt-sol
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The categories of this paper are: solv-int
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The categories of this paper are: hep-ex
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The categories of this paper are: econ
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The categories of this paper are: q-alg
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The categories of this paper are: astro-ph
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The categories of this paper are: acc-phys
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The categories of this paper are: math-ph
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The categories of this paper are: q-bio
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The categories of this paper are: hep-ph