Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Theory of Current-Driven Domain Wall Motion: A Poorman's Approach   A self-contained theory of the domain wall dynamics in ferromagnets under
finite electric current is presented.
  The current is shown to have two effects; one is momentum transfer, which is
proportional to the charge current and wall resistivity ($\rhow$), and the
other is spin transfer, proportional to spin current.
  For thick walls, as in metallic wires, the latter dominates and the threshold
current for wall motion is determined by the hard-axis magnetic anisotropy,
except for the case of very strong pinning.
  For thin walls, as in nanocontacts and magnetic semiconductors, the
momentum-transfer effect dominates, and the threshold current is proportional
to $\Vz/\rhow$, $\Vz$ being the pinning potential.

10
The categories of this paper are: q-bio
23
The categories of this paper are: solv-int
13
The categories of this paper are: quant-ph
36
The categories of this paper are: cmp-lg
29
The categories of this paper are: funct-an
33
The categories of this paper are: plasm-ph
15
The categories of this paper are: nucl-ex
30
The categories of this paper are: q-alg
16
The categories of this paper are: stat
17
The categories of this paper are: q-fin
3
The categories of this paper are: physics
26
The categories of this paper are: bayes-an
8
The categories of this paper are: hep-ex
37
The categories of this paper are: supr-con
11
The categories of this paper are: hep-lat
0
The categories of this paper are: hep-ph