Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Asymmetric Si-slot Coupler with Nonreciprocal Response Based on Graphene
  Saturable Absorption   We present the study of a proof-of-concept integrated device that can be used
as a nonlinear broadband isolator. The device is based on the asymmetric
loading of a highly-confining silicon-slot photonic coupler with graphene
layers, whose ultrafast and low-threshold saturable absorption can be exploited
for nonreciprocal transmission between the cross-ports of the coupler. The
structure is essentially a non-Hermitian system, whose exceptional points are
briefly discussed. The nonlinear device is modeled with a coupled Schrodinger
equation system whose validity is checked by full-vector finite element-based
beam-propagation method simulations in CW. The numerically computed performance
reveals a nonreciprocal intensity range (NRIR) in the vicinity of 100 mW peak
power with a bandwidth spanning tens of nanometers, from CW down to ps-long
pulses. Finally, the combination of saturable absorption and self-phase
modulation (Kerr effect) in graphene is studied, indicating the existence of
two NRIR with opposite directionality.

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The categories of this paper are: hep-th
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The categories of this paper are: solv-int
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The categories of this paper are: patt-sol
37
The categories of this paper are: supr-con
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The categories of this paper are: bayes-an
16
The categories of this paper are: stat
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The categories of this paper are: nlin
0
The categories of this paper are: hep-ph
4
The categories of this paper are: cond-mat
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The categories of this paper are: astro-ph
34
The categories of this paper are: chem-ph
21
The categories of this paper are: adap-org
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The categories of this paper are: q-fin
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The categories of this paper are: eess
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The categories of this paper are: cmp-lg
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The categories of this paper are: atom-ph