Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Current-induced spin polarization and the spin Hall effect: a
  quasiclassical approach   The quasiclassical Green function formalism is used to describe charge and
spin dynamics in the presence of spin-orbit coupling. We review the results
obtained for the spin Hall effect on restricted geometries. The role of
boundaries is discussed in the framework of spin diffusion equations.

5
The categories of this paper are: gr-qc
21
The categories of this paper are: adap-org
10
The categories of this paper are: q-bio
9
The categories of this paper are: nlin
11
The categories of this paper are: hep-lat
29
The categories of this paper are: funct-an
17
The categories of this paper are: q-fin
30
The categories of this paper are: q-alg
0
The categories of this paper are: hep-ph
14
The categories of this paper are: math-ph
19
The categories of this paper are: eess
12
The categories of this paper are: nucl-th
24
The categories of this paper are: dg-ga
22
The categories of this paper are: chao-dyn
28
The categories of this paper are: alg-geom
34
The categories of this paper are: chem-ph