Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Scattering of Dirac electrons from a skyrmion: emergence of robust skew
  scattering   We study electron scattering from a closed magnetic structure embedded in the
top surface of a topological insulator (TI). Outside the structure there is a
uniform layer of ferromagnetic insulator (FMI), leading to a positive effective
mass for the Dirac electrons. The mass inside can be engineered to be negative,
leading to a skyrmion structure. The geometric shape of the structure can be
circular or deformed, leading to integrable or chaotic dynamics, respectively,
in the classical limit. For a circular structure, the relativistic quantum
scattering characteristics can be calculated analytically. For a deformed
structure, we develop an efficient numerical method, the multiple multipole
method, to solve the scattering wavefunctions. We find that anomalous Hall
effect as characterized by strong skew scattering can arise, which is robust
against structural deformation due to the resonant modes. In the short (long)
wavelength regime, the resonant modes manifest themselves as confined vortices
(excited edge states). The origin of the resonant states is the spin phase
factor of massive Dirac electrons at the skyrmion boundary. Further, in the
short wavelength regime, for a circular skyrmion, a large number of angular
momentum channels contribute to the resonant modes. In this regime, in
principle, classical dynamics are relevant, but we find that geometric
deformations, even those as severe as leading to fully developed chaos, have
little effect on the resonant modes. The vortex structure of the resonant
states makes it possible to electrically ``charge'' the skyrmion, rendering
feasible to manipulate its motion electrically. In the long wavelength regime,
only the lowest angular momentum channels contribute to the resonant modes,
making the skew scattering sharply directional. These phenomena may find
applications for information storage and in Hall devices based on dynamic
skyrmion.

11
The categories of this paper are: hep-lat
16
The categories of this paper are: stat
12
The categories of this paper are: nucl-th
22
The categories of this paper are: chao-dyn
29
The categories of this paper are: funct-an
10
The categories of this paper are: q-bio
23
The categories of this paper are: solv-int
35
The categories of this paper are: mtrl-th
37
The categories of this paper are: supr-con
32
The categories of this paper are: atom-ph
36
The categories of this paper are: cmp-lg
34
The categories of this paper are: chem-ph
3
The categories of this paper are: physics
18
The categories of this paper are: econ
6
The categories of this paper are: astro-ph
30
The categories of this paper are: q-alg