Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Surface states and Rashba-type spin polarization in antiferromagnetic
  MnBi$_2$Te$_4$   The layered van der Waals antiferromagnet MnBi$_2$Te$_4$ has been predicted
to combine the band ordering of archetypical topological insulators such as
Bi$_2$Te$_3$ with the magnetism of Mn, making this material a viable candidate
for the realization of various magnetic topological states. We have
systematically investigated the surface electronic structure of
MnBi$_2$Te$_4$(0001) single crystals by use of spin- and angle-resolved
photoelectron spectroscopy experiments. In line with theoretical predictions,
the results reveal a surface state in the bulk band gap and they provide
evidence for the influence of exchange interaction and spin-orbit coupling on
the surface electronic structure.

36
The categories of this paper are: cmp-lg
1
The categories of this paper are: cs
33
The categories of this paper are: plasm-ph
20
The categories of this paper are: acc-phys
2
The categories of this paper are: math
22
The categories of this paper are: chao-dyn
23
The categories of this paper are: solv-int
35
The categories of this paper are: mtrl-th
28
The categories of this paper are: alg-geom
29
The categories of this paper are: funct-an
27
The categories of this paper are: comp-gas
19
The categories of this paper are: eess
30
The categories of this paper are: q-alg
31
The categories of this paper are: ao-sci
7
The categories of this paper are: hep-th
8
The categories of this paper are: hep-ex