Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Dirac electrons and domain walls: a realization in junctions of
  ferromagnets and topological insulators   We study a system of Dirac electrons with finite density of charge carriers
coupled to an external electromagnetic field in two spatial dimensions, with a
domain wall (DW) mass term. The interface between a thin-film ferromagnet and a
three-dimensional topological insulator provides a condensed-matter realization
of this model, when an out-of-plane domain wall magnetization is coupled to the
TI surface states. We show how, for films with very weak intrinsic in-plane
anisotropies, the torque generated by the edge electronic current flowing along
the DW competes with an effective in-plane anisotropy energy, induced by
quantum fluctuations of the chiral electrons bound to the wall, in a mission to
drive the internal angle of the DW from a Bloch configuration towards a N\'eel
configuration. Both the edge current and the induced anisotropy contribute to
stabilize the internal angle, so that for weak intrinsic in-plane anisotropies
DW motion is still possible without suffering from an extremely early Walker
breakdown.

5
The categories of this paper are: gr-qc
21
The categories of this paper are: adap-org
17
The categories of this paper are: q-fin
9
The categories of this paper are: nlin
27
The categories of this paper are: comp-gas
32
The categories of this paper are: atom-ph
6
The categories of this paper are: astro-ph
25
The categories of this paper are: patt-sol
24
The categories of this paper are: dg-ga
15
The categories of this paper are: nucl-ex
22
The categories of this paper are: chao-dyn
13
The categories of this paper are: quant-ph
35
The categories of this paper are: mtrl-th
14
The categories of this paper are: math-ph
28
The categories of this paper are: alg-geom
33
The categories of this paper are: plasm-ph