Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Mechanisms for Sub-Gap Optical Conductivity in Herbertsmithite   Recent terahertz conductivity measurements observed low-power-law frequency
dependence of optical conduction within the Mott gap of the Kagome lattice
spin-liquid candidate Herbertsmithite. We investigate mechanisms for this
observed sub-gap conductivity for two possible scenarios in which the
ground-state is described by: 1) a U(1) Dirac spin-liquid with emergent
fermionic spinons or 2) a nearly critical Z2 spin-liquid in the vicinity of a
continuous quantum phase transition to magnetic order. We identify new
mechanisms for optical-absorption via magneto-elastic effects and spin- orbit
coupling. In addition, for the Dirac spin-liquid scenario, we establish an
explicit microscopic origin for previously proposed absorption mechanisms based
on slave-particle effective field theory descriptions.

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The categories of this paper are: quant-ph
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The categories of this paper are: chao-dyn
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The categories of this paper are: chem-ph
31
The categories of this paper are: ao-sci
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The categories of this paper are: funct-an
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The categories of this paper are: adap-org
2
The categories of this paper are: math
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The categories of this paper are: nlin
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The categories of this paper are: alg-geom
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The categories of this paper are: mtrl-th
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The categories of this paper are: hep-th
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The categories of this paper are: nucl-ex
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The categories of this paper are: econ
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The categories of this paper are: eess
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The categories of this paper are: cs
32
The categories of this paper are: atom-ph