Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Lead Halide Perovskite based Dynamic Metasurfaces   Lead halide perovskites (MAPbX3) are known to have high refractive index and
controllable bandgap, making them attractive for all-dielectric and tunable
metasurfaces. Till now, perovskite metasurfaces have only been used in
structural colors. More interesting meta-devices with 2{\pi} phase control are
still absent. Here we experimentally demonstrate the MAPbX3 perovskite based
metasurfaces with a complete control of phase shift in a reflection mode. By
utilizing MAPbBr3 cut-wires as meta-atoms on a ground metal film, we find that
the MAPbBr3 perovskite metasurface can produce full phase control from 0 to
2{\pi} and high reflection efficiency simultaneously. Consequently,
high-efficiency polarization conversion, anomalous reflection and meta-hologram
have been successfully produced. Most interestingly, the bandgap of MAPbX3
perovskite can be post-synthetically and reversibly tuned via anion exchange,
providing a new approach to dynamically control of the all-dielectric
meta-devices with novel function such as anomalous reflection and hologram et
al.

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The categories of this paper are: gr-qc
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The categories of this paper are: cmp-lg
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The categories of this paper are: mtrl-th
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The categories of this paper are: hep-th
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The categories of this paper are: funct-an
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The categories of this paper are: comp-gas
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The categories of this paper are: q-alg
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The categories of this paper are: hep-ph
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The categories of this paper are: astro-ph
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The categories of this paper are: adap-org
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The categories of this paper are: bayes-an
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The categories of this paper are: atom-ph
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The categories of this paper are: plasm-ph
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The categories of this paper are: dg-ga
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The categories of this paper are: patt-sol
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The categories of this paper are: econ