Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Topological Order Parameters for Interacting Topological Insulators   We propose a topological order parameter for interacting topological
insulators, expressed in terms of the full Green's functions of the interacting
system. We show that it is exactly quantized for a time reversal invariant
topological insulator, and it can be experimentally measured through the
topological magneto-electric effect. This topological order parameter can be
applied to both interacting and disordered systems, and used for determining
their phase diagrams.

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The categories of this paper are: comp-gas
3
The categories of this paper are: physics
36
The categories of this paper are: cmp-lg
17
The categories of this paper are: q-fin
35
The categories of this paper are: mtrl-th
21
The categories of this paper are: adap-org
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The categories of this paper are: stat
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The categories of this paper are: hep-lat
10
The categories of this paper are: q-bio
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The categories of this paper are: quant-ph
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The categories of this paper are: atom-ph
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The categories of this paper are: solv-int
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The categories of this paper are: supr-con
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The categories of this paper are: acc-phys
6
The categories of this paper are: astro-ph
22
The categories of this paper are: chao-dyn