Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Metal--topological-insulator transition in the quantum kicked rotator
  with Z2 symmetry   The quantum kicked rotator is a periodically driven dynamical system with a
metal-insulator transition. We extend the model so that it includes phase
transitions between a metal and a topological insulator, in the universality
class of the quantum spin Hall effect. We calculate the Z2 topological
invariant using a scattering formulation that remains valid in the presence of
disorder. The scaling laws at the phase transition can be studied efficiently
by replacing one of the two spatial dimensions with a second incommensurate
driving frequency. We find that the critical exponent does not depend on the
topological invariant, in agreement with earlier independent results from the
network model of the quantum spin Hall effect.

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The categories of this paper are: astro-ph
10
The categories of this paper are: q-bio
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The categories of this paper are: q-fin
29
The categories of this paper are: funct-an
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The categories of this paper are: hep-th
5
The categories of this paper are: gr-qc
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The categories of this paper are: solv-int
1
The categories of this paper are: cs
9
The categories of this paper are: nlin
18
The categories of this paper are: econ
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The categories of this paper are: stat
14
The categories of this paper are: math-ph
27
The categories of this paper are: comp-gas
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The categories of this paper are: acc-phys
30
The categories of this paper are: q-alg
26
The categories of this paper are: bayes-an