Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Hopping versus bulk conductivity in transparent oxides: 12CaO.7Al2O3   First-principles calculations of the mayenite-based oxide,
[Ca12Al14O32]{2+}(2e-), reveal the mechanism responsible for its high
conductivity. A detailed comparison of the electronic and optical properties of
this material with those of the recently discovered novel transparent
conducting oxide, H-doped UV-activated Ca12Al14O33, allowed us to conclude that
the enhanced conductivity in [Ca12Al14O32]{2+}(2e-) is achieved by elimination
of the Coulomb blocade of the charge carriers. This results in a transition
from variable range hopping behavior with a Coulomb gap in H-doped
UV-irradiated Ca12Al14O33 to bulk conductivity in [Ca12Al14O32]{2+}(2e-).
Further, the high degree of the delocalization of the conduction electrons
obtained in [Ca12Al14O32]{2+}(2e-) indicate that it cannot be classified as an
electride, originally suggested.

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The categories of this paper are: q-alg
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The categories of this paper are: cmp-lg
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The categories of this paper are: nlin
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The categories of this paper are: eess
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The categories of this paper are: hep-ex
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The categories of this paper are: hep-th
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The categories of this paper are: chao-dyn
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The categories of this paper are: acc-phys
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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: patt-sol
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The categories of this paper are: math-ph
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The categories of this paper are: chem-ph
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The categories of this paper are: alg-geom
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The categories of this paper are: cs