Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Effect of Coulomb interaction on the two-dimensional electronic
  structure of the van der Waals ferromagnet Cr$_2$Ge$_2$Te$_6$   In order to investigate the electronic properties of the semiconducting van
der Waals ferromagnet Cr$_2$Ge$_2$Te$_6$ (CGT), where ferromagnetic layers are
bonded through van der Waals forces, we have performed angle-resolved
photoemission spectroscopy (ARPES) measurements and density-functional-theory
(DFT+U) calculations. The valence-band maximum at the {\Gamma} point is located
$\sim$ 0.2 eV below the Fermi level, consistent with the semiconducting
property of CGT. Comparison of the experimental density of states with the DFT
calculation has suggested that Coulomb interaction between the Cr 3d electrons
U$_{\rm eff}$ $\sim$ 1.1 eV. The DFT+U calculation indicates that magnetic
coupling between Cr atoms within the layer is ferromagnetic if Coulomb U $_{\rm
eff}$ is smaller than 3.0 eV and that the inter-layer coupling is ferromagnetic
below U$_{\rm eff}$ $\sim$ 1.0 eV. We therefore conclude that, for U$_{\rm
eff}$ deduced by the experiment, the intra-layer Cr-Cr coupling is
ferromagnetic and the inter-layer coupling is near the boundary between
ferromagnetic and antiferromagnetic, which means experimentally deduced U$_{\rm
eff}$ is consistent with theoretical ferromagnetic condition.

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The categories of this paper are: acc-phys
3
The categories of this paper are: physics
35
The categories of this paper are: mtrl-th
26
The categories of this paper are: bayes-an
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The categories of this paper are: solv-int
1
The categories of this paper are: cs
37
The categories of this paper are: supr-con
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The categories of this paper are: quant-ph
14
The categories of this paper are: math-ph
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The categories of this paper are: q-bio
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The categories of this paper are: patt-sol
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The categories of this paper are: funct-an
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The categories of this paper are: hep-ph
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The categories of this paper are: nucl-th
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The categories of this paper are: alg-geom
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The categories of this paper are: q-fin