Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Mass acquisition of Dirac fermions in Cr-doped topological insulator
  Sb2Te3 films   We introduce time-reversal-symmetry breaking by doping Cr atoms into the
topmost quintuple layer or into the bulk of Sb2Te3 thin films. We find that
even at a high Cr-doping level the Landau level spectrum keeps a good quality,
enabling the first demonstration of deviation of the zero-mode Landau level,
induced by the acquisition of a mass term in the surface states in the presence
of surface or bulk magnetic doping. The magnitude of the mass term in the
surface states increases with increasing Cr-doping level. Our observation
suggests Cr-doped Sb2Te3 is a promising candidate for the realization of the
proposed novel magnetoelectric effects.

23
The categories of this paper are: solv-int
30
The categories of this paper are: q-alg
0
The categories of this paper are: hep-ph
22
The categories of this paper are: chao-dyn
35
The categories of this paper are: mtrl-th
28
The categories of this paper are: alg-geom
24
The categories of this paper are: dg-ga
26
The categories of this paper are: bayes-an
2
The categories of this paper are: math
16
The categories of this paper are: stat
10
The categories of this paper are: q-bio
34
The categories of this paper are: chem-ph
3
The categories of this paper are: physics
31
The categories of this paper are: ao-sci
25
The categories of this paper are: patt-sol
7
The categories of this paper are: hep-th