Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Tha angular spectrum representation of vectorial laser beams   The angular spectrum of a vectorial laser beam is expressed in terms of an
intrinsic coordinate system instead of the usual Cartesian laboratory
coordinates. This switch leads to simple, elegant and new expressions such as
for the angular spectrum of the Hertz vector corresponding to the
electromagnetic fields. As an application of this approach, we consider axially
symmetric vector beams, showing non-diffracting properties of these beams,
without invoking the paraxial approximation. Further, we indicate the relevance
of the method for analyzing nonparaxial resonators, such as microresonators

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The categories of this paper are: hep-ex
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The categories of this paper are: astro-ph
35
The categories of this paper are: mtrl-th
36
The categories of this paper are: cmp-lg
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The categories of this paper are: math-ph
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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: q-fin
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The categories of this paper are: nucl-ex
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The categories of this paper are: ao-sci
29
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: hep-th
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The categories of this paper are: math
0
The categories of this paper are: hep-ph