Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Giant terahertz near-field enhancement by two-dimensional plasmons   We consider a periodically gated two-dimensional electron system, with a
central gate finger biased independently creating a tunable plasmonic cavity in
a planar plasmonic crystal. We demonstrate that the plasmons resonantly excited
in the periodic plasmonic lattice by incident terahertz radiation can strongly
pump the cavity plasmon modes leading to a deep sub-wavelength concentration of
terahertz energy with giant electric field enhancement factor up to 10000.

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The categories of this paper are: supr-con
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The categories of this paper are: ao-sci
12
The categories of this paper are: nucl-th
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The categories of this paper are: stat
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The categories of this paper are: comp-gas
4
The categories of this paper are: cond-mat
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The categories of this paper are: acc-phys
5
The categories of this paper are: gr-qc
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The categories of this paper are: atom-ph
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The categories of this paper are: eess
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The categories of this paper are: mtrl-th
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The categories of this paper are: chem-ph
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The categories of this paper are: adap-org
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The categories of this paper are: q-alg
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The categories of this paper are: cmp-lg
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The categories of this paper are: solv-int