Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Spin and orbital Hall effects for diffracting optical beams in
  gradient-index media   We examine the evolution of paraxial beams carrying intrinsic spin and
orbital angular momenta (AM) in gradient-index media. A parabolic-type equation
is derived which describes the beam diffraction in curvilinear coordinates
accompanying the central ray. The center of gravity of the beam experiences
transverse AM-dependent deflections -- the spin and orbital Hall effects. The
spin Hall effect generates a transverse translation of the beam as a whole, in
precise agreement with recent geometrical optics predictions. At the same time,
the orbital Hall effect is significantly affected by the diffraction in the
inhomogeneous medium and is accompanied by changes in the intrinsic orbital AM
and deformations of the beam.

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The categories of this paper are: solv-int
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The categories of this paper are: chao-dyn
6
The categories of this paper are: astro-ph
11
The categories of this paper are: hep-lat
4
The categories of this paper are: cond-mat
13
The categories of this paper are: quant-ph
34
The categories of this paper are: chem-ph
12
The categories of this paper are: nucl-th
37
The categories of this paper are: supr-con
21
The categories of this paper are: adap-org
36
The categories of this paper are: cmp-lg
33
The categories of this paper are: plasm-ph
9
The categories of this paper are: nlin
20
The categories of this paper are: acc-phys
2
The categories of this paper are: math
32
The categories of this paper are: atom-ph