Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Photoexcitation of atoms by cylindrically polarized Laguerre-Gaussian
  beams   We analyze the photo-excitation of atoms with a single valence electron by
cylindrically polarized Laguerre-Gaussian beams. Theoretical analysis is
performed within the framework of first-order perturbation theory and by
expanding the vector potential of the Laguerre-Gaussian beam in terms of its
multipole components. For cylindrically polarized Laguerre-Gaussian beams, we
show that the (magnetic) sub-components of electric-quadrupole field vary
significantly in the beam cross-section with beam waist and radial distance
from the beam axis. We discuss the influence of varying magnetic multipole
component in the beam cross-section on the sub-level population of a localized
atomic target. In addition, we calculate the total excitation rate of electric
quadrupole transition ($4s \;^{2}S_{1/2} \rightarrow 3d \;^{2}D_{5/2}$) in a
mesoscopic target of Ca$^{+}$ ion. These calculations shows that the total rate
of excitation is sensitive to the beam waist and the distance between center of
the target and the beam axis. However, the excitation by cylindrically
polarized Laguerre-Gaussian beam is found more efficient in driving electric
quadrupole transition in the mesoscopic atomic target than the circularly
polarized beams.

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The categories of this paper are: bayes-an
7
The categories of this paper are: hep-th
22
The categories of this paper are: chao-dyn
10
The categories of this paper are: q-bio
15
The categories of this paper are: nucl-ex
14
The categories of this paper are: math-ph
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The categories of this paper are: solv-int
30
The categories of this paper are: q-alg
2
The categories of this paper are: math
9
The categories of this paper are: nlin
0
The categories of this paper are: hep-ph
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The categories of this paper are: hep-lat
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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: quant-ph
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The categories of this paper are: alg-geom