Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Robust acoustic cloaking with density-near-zero materials   Using the phenomenon of extraordinary sound transmission (EST) through
artificially constructed density-near-zero (DNZ) materials, we propose an
alternative approach to realize a very robust acoustic cloaking, which includes
one absorber and one projector connected by an energy channel. The elementary
unit cell is made of one single-piece homogeneous copper, but it well maintains
both the original planar wavefront and the nearly perfect one-dimensional
transmission, in the presence of any inserted objects. Furthermore, the overall
cloaked space can be increased, designed, and distributed by arbitrarily
assembling additional DNZ cells without any upper limit in the total cloaking
volume. We demonstrate acoustic cloaking by different combinations of DNZ cells
in free space as well as in acoustic waveguides, which enables any objects
inside the cells imperceptible along undistorted sound paths.

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The categories of this paper are: ao-sci
32
The categories of this paper are: atom-ph
9
The categories of this paper are: nlin
25
The categories of this paper are: patt-sol
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The categories of this paper are: chao-dyn
12
The categories of this paper are: nucl-th
6
The categories of this paper are: astro-ph
7
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: supr-con
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The categories of this paper are: funct-an
30
The categories of this paper are: q-alg
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The categories of this paper are: chem-ph
36
The categories of this paper are: cmp-lg
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The categories of this paper are: alg-geom
18
The categories of this paper are: econ