Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Chiral transport and electronic correlations in surface states of HfNiSn
  single crystals   In most topological insulators, the valence and conduction band appear in
reverse or inverted order compared to an equivalent insulator with isolated
atoms. Here, we explore a different route towards topologically nontrivial
states that may arise from metallic states present on the surface of bulk
insulators without such band inversion. High-quality single crystals of HfNiSn
show surface transport with weak anti-localization, consistent with a
two-dimensional metallic state in the presence of strong spin-orbit coupling.
Nonlinear I(V) curves indicate electronic correlations related to a chiral,
nonlocal transport component that is qualitatively similar to a quantum Hall
edge state, yet in the absence of external magnetic fields. The correlations
themselves may play a decisive role in creating an apparent topologically
nontrivial state on the HfNiSn surface.

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The categories of this paper are: astro-ph
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The categories of this paper are: mtrl-th
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The categories of this paper are: plasm-ph
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The categories of this paper are: dg-ga
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The categories of this paper are: quant-ph
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The categories of this paper are: acc-phys
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The categories of this paper are: q-fin
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The categories of this paper are: physics
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The categories of this paper are: ao-sci
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The categories of this paper are: q-bio
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The categories of this paper are: hep-th
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The categories of this paper are: hep-ex
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The categories of this paper are: nlin
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The categories of this paper are: math
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The categories of this paper are: supr-con
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The categories of this paper are: chem-ph