Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Collection of Propagating Electromagnetic Fields by Uncoated Probe   Understanding light-matter interaction at the nanoscale by observation of
fine details of electromagnetic fields is achieved by bringing nanoscale probes
into the nearfield of light sources, capturing information that is lost in the
far field. Although metal coated probes are often used for nearfield
microscopy, they strongly perturb the electromagnetic fields under study. Here,
through experiment and simulation, we detail light collection by uncoated fiber
probes, which minimize such perturbation. Second-harmonic light from
intensely-irradiated sub-wavelength sub-surface features was imaged to avoid
otherwise dominating fundamental light background, yielding clear nearfield
details through a 50 nm aperture uncoated probe with ~23 nm optical resolution.
Simulations shows how a metallic coating distorts optical nearfields and limits
optical coupling into the probe in comparison to an uncoated probe.

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The categories of this paper are: funct-an
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The categories of this paper are: hep-lat
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The categories of this paper are: chem-ph
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The categories of this paper are: supr-con
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The categories of this paper are: comp-gas
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The categories of this paper are: nucl-ex
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The categories of this paper are: acc-phys
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The categories of this paper are: hep-ex
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The categories of this paper are: nlin
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The categories of this paper are: bayes-an
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The categories of this paper are: eess
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The categories of this paper are: adap-org
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The categories of this paper are: stat
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The categories of this paper are: ao-sci
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The categories of this paper are: astro-ph
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The categories of this paper are: q-fin