Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Efficient Modal Decomposition of Vortex Beams via Holographically
  Reconstructed Phase   We use phase-shifting digital holography to measure the amplitude and phase
of twisted light. In our experiment, a spatial light modulator generates the
studied vortex beams in addition to a co-propagating reference beam with a
controllable relative phase. We show complex field measurements for single and
superposition Laguerre Gaussian (LG) modes, demonstrate full modal
decompositions into LG and orbital angular momentum (OAM) power spectral bases,
provide error analysis and demonstrate high insensitivity to detector
misalignment to show the robustness of the technique. This enables rapid
determination of OAM spectra with low uncertainty, allowing us to report the
first vortex beams with 99.9% purity.

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The categories of this paper are: plasm-ph
6
The categories of this paper are: astro-ph
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The categories of this paper are: atom-ph
11
The categories of this paper are: hep-lat
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The categories of this paper are: econ
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The categories of this paper are: stat
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The categories of this paper are: q-alg
0
The categories of this paper are: hep-ph
10
The categories of this paper are: q-bio
35
The categories of this paper are: mtrl-th
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The categories of this paper are: patt-sol
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The categories of this paper are: math
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The categories of this paper are: nucl-th
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The categories of this paper are: gr-qc
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The categories of this paper are: hep-th
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The categories of this paper are: cmp-lg