Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Two-Dimensional Electrostatic Lattices for Indirect Excitons   We report on a method for the realization of two-dimensional electrostatic
lattices for excitons using patterned interdigitated electrodes. Lattice
structure is set by the electrode pattern and depth of the lattice potential is
controlled by applied voltages. We demonstrate square, hexagonal, and honeycomb
lattices created by this method.

31
The categories of this paper are: ao-sci
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The categories of this paper are: bayes-an
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The categories of this paper are: patt-sol
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The categories of this paper are: mtrl-th
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The categories of this paper are: nucl-th
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The categories of this paper are: supr-con
10
The categories of this paper are: q-bio
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The categories of this paper are: atom-ph
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The categories of this paper are: comp-gas
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The categories of this paper are: stat
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The categories of this paper are: solv-int
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The categories of this paper are: econ
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The categories of this paper are: astro-ph
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The categories of this paper are: math
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The categories of this paper are: gr-qc
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The categories of this paper are: adap-org