Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Transformation-optics macroscopic visible-light cloaking beyond two
  dimensions   Transformation optics, a recent geometrical design strategy of controlling
light by combining Maxwell's principles of electromagnetism with Einstein's
general relativity, promises without precedent an invisibility cloaking device
that can render a macroscopic object invisible in three dimensions. However,
most previous proof-of-concept transformation-optics cloaking devices focused
predominantly on two dimensions, whereas detection of a macroscopic object
along its third dimension was always unfailing. Here, we report the first
experimental demonstration of transformation-optics macroscopic visible-light
cloaking beyond two dimensions. This almost-three-dimensional cloak exhibits
three-dimensional (3D) invisibility for illumination near its center (i.e. with
a limited field of view), and its ideal wide-angle invisibility performance is
preserved in multiple two-dimensional (2D) planes intersecting in the 3D space.
Both light ray trajectories and optical path lengths have been verified
experimentally at the macroscopic scale, which provides unique evidence on the
geometrical nature of transformation optics.

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The categories of this paper are: plasm-ph
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The categories of this paper are: cmp-lg
18
The categories of this paper are: econ
24
The categories of this paper are: dg-ga
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The categories of this paper are: mtrl-th
10
The categories of this paper are: q-bio
2
The categories of this paper are: math
13
The categories of this paper are: quant-ph
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The categories of this paper are: eess
1
The categories of this paper are: cs
9
The categories of this paper are: nlin
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The categories of this paper are: math-ph
16
The categories of this paper are: stat
4
The categories of this paper are: cond-mat
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The categories of this paper are: patt-sol
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The categories of this paper are: atom-ph