Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Magnetoelectric Response of the Time-Reversal Invariant Helical Metal   We derive compact analytical expressions for the coupled spin-charge
susceptibility of a clean helical metal at the surface of a three dimensional
topological insulator (TI). These expressions lead to unconventional
non-collinear RKKY interactions between two impurity magnetic moments placed on
the surface of a TI, and predict the generation of electric currents by
time-dependent magnetic moments. We determine the influence of gate and bias
voltages on the interlayer exchange coupling between two single-domain
ferromagnetic monolayers deposited on top of a TI.

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The categories of this paper are: quant-ph
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The categories of this paper are: hep-lat
1
The categories of this paper are: cs
29
The categories of this paper are: funct-an
10
The categories of this paper are: q-bio
23
The categories of this paper are: solv-int
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The categories of this paper are: acc-phys
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The categories of this paper are: alg-geom
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The categories of this paper are: atom-ph
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The categories of this paper are: ao-sci
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The categories of this paper are: dg-ga
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The categories of this paper are: q-fin
2
The categories of this paper are: math
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The categories of this paper are: bayes-an
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The categories of this paper are: eess
8
The categories of this paper are: hep-ex