Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Current response of a topological insulator to a static Zeeman field   We study the magnetoelectric coupling at the surface of a topological
insulator. We are in particular interested in the surface current induced by a
static Zeeman/exchange field. This surface current can be related to the
orbital magnetization of the system. For an insulator with zero Chern number,
the orbital magnetization is independent of the details at the boundary. With
the appearance of surface states in the topological insulator, it is not
immediately obvious if the response is not affected by the conditions at the
surface. We investigate this question using exact diagonalization to a lattice
model. By applying a time-reversal symmetry-breaking term near the boundary, no
matter if the surface states are gapped out, we still find no change in the
surface current. This arises from cancelations between Pauli and Van-Vleck
contributions between surface and bulk scattering states. We also show that the
surface current response is independent of the chemical potential when it is
within the bulk gap. Our results are consistent with the claim that orbital
magnetization is a bulk property.

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The categories of this paper are: bayes-an
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The categories of this paper are: eess
12
The categories of this paper are: nucl-th
17
The categories of this paper are: q-fin
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The categories of this paper are: q-alg
11
The categories of this paper are: hep-lat
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The categories of this paper are: funct-an
32
The categories of this paper are: atom-ph
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The categories of this paper are: patt-sol
9
The categories of this paper are: nlin
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The categories of this paper are: dg-ga
10
The categories of this paper are: q-bio
5
The categories of this paper are: gr-qc
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The categories of this paper are: hep-ex
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The categories of this paper are: stat
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The categories of this paper are: nucl-ex