Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Enhanced nonlinear optical response of single metal-dielectric
  nanocavities resonating in the near-infrared   Harmonic generation mechanisms are of great interest in nanoscience and
nanotechnology, since they allow generating visible light by using
near-infrared radiation, which is particularly suitable for its endless
applications in bio-nanophotonics and opto-electronics. In this context,
multilayer metal-dielectric nanocavities are widely used for light confinement
and waveguiding at the nanoscale. They exhibit intense and localized resonances
that can be conveniently tuned in the near-infrared and are therefore ideal for
enhancing nonlinear effects in this spectral range. In this work, we
experimentally investigate the nonlinear optical response of multilayer
metal-dielectric nanocavities. By engineering their absorption efficiency and
exploiting their intrinsic interface-induced symmetry breaking, we achieve one
order of magnitude higher second-harmonic generation efficiency compared to
gold nanostructures featuring the same geometry and resonant behavior. In
particular, while the third order nonlinear susceptibility is comparable with
that of bulk Au, we estimate a second order nonlinear susceptibility of the
order of 1 pm/V, which is comparable with that of typical nonlinear crystals.
We envision that our system, which combines the advantages of both plasmonic
and dielectric materials, might enable the realization of composite and
multi-functional nano-systems for an efficient manipulation of nonlinear
optical processes at the nanoscale.

14
The categories of this paper are: math-ph
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The categories of this paper are: quant-ph
31
The categories of this paper are: ao-sci
11
The categories of this paper are: hep-lat
5
The categories of this paper are: gr-qc
33
The categories of this paper are: plasm-ph
27
The categories of this paper are: comp-gas
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The categories of this paper are: chem-ph
17
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: stat
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The categories of this paper are: solv-int
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The categories of this paper are: alg-geom
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The categories of this paper are: astro-ph
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The categories of this paper are: funct-an
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The categories of this paper are: chao-dyn