Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Dielectric Optical-Controlled Magnifying Lens by Nonlinear Negative
  Refraction   A simple optical lens plays an important role for exploring the microscopic
world in science and technology by refracting light with tailored spatially
varying refractive index. Recent advancements in nanotechnology enable novel
lenses, such as, superlens, hyperlens, Luneburg lens, with sub-wavelength
resolution capabilities by specially designing materials' refractive indices
with meta-materials and transformation optics. However, these artificially
nano/micro engineered lenses usually suffer high losses from metals and are
highly demanding in fabrication. Here we experimentally demonstrate for the
first time a nonlinear dielectric magnifying lens using negative refraction by
degenerate four-wave mixing in a plano-concave glass slide, obtaining magnified
images. Moreover, we transform a nonlinear flat lens into a magnifying lens by
introducing transformation optics into nonlinear regime, achieving an
all-optical controllable lensing effect through nonlinear wave mixing, which
may have many potential applications in microscopy and imaging science.

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The categories of this paper are: math
21
The categories of this paper are: adap-org
36
The categories of this paper are: cmp-lg
14
The categories of this paper are: math-ph
29
The categories of this paper are: funct-an
23
The categories of this paper are: solv-int
13
The categories of this paper are: quant-ph
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The categories of this paper are: gr-qc
24
The categories of this paper are: dg-ga
10
The categories of this paper are: q-bio
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The categories of this paper are: hep-lat
20
The categories of this paper are: acc-phys
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The categories of this paper are: nlin
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The categories of this paper are: hep-ex
16
The categories of this paper are: stat
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The categories of this paper are: cond-mat