Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: High-precision realization of robust quantum anomalous Hall state in a
  hard ferromagnetic topological insulator   The discovery of the quantum Hall (QH) effect led to the realization of a
topological electronic state with dissipationless currents circulating in one
direction along the edge of a two dimensional electron layer under a strong
magnetic field. The quantum anomalous Hall (QAH) effect shares a similar
physical phenomenon as the QH effect, whereas its physical origin relies on the
intrinsic spin-orbit coupling and ferromagnetism.Here we report the
experimental observation of the QAH state in V-doped (Bi,Sb)2Te3 films with the
zero-field longitudinal resistance down to 0.00013+-0.00007h/e2 (~3.35+-1.76
ohm), Hall conductance reaching 0.9998+-0.0006e2/h and the Hall angle becoming
as high as 89.993+-0.004degree at T=25mK. Further advantage of this system
comes from the fact that it is a hard ferromagnet with a large coercive field
(Hc>1.0T) and a relative high Curie temperature. This realization of robust QAH
state in hard FMTIs is a major step towards dissipationless electronic
applications without external fields.

26
The categories of this paper are: bayes-an
14
The categories of this paper are: math-ph
11
The categories of this paper are: hep-lat
27
The categories of this paper are: comp-gas
29
The categories of this paper are: funct-an
3
The categories of this paper are: physics
31
The categories of this paper are: ao-sci
10
The categories of this paper are: q-bio
19
The categories of this paper are: eess
35
The categories of this paper are: mtrl-th
16
The categories of this paper are: stat
17
The categories of this paper are: q-fin
28
The categories of this paper are: alg-geom
22
The categories of this paper are: chao-dyn
13
The categories of this paper are: quant-ph
18
The categories of this paper are: econ