Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Spin-Orbit Coupling in Iridium-Based 5d Compounds Probed by X-ray
  Absorption Spectroscopy   We have performed x-ray absorption spectroscopy (XAS) measurements on a
series of Ir-based 5d transition metal compounds, including Ir, IrCl3, IrO2,
Na2IrO3, Sr2IrO4, and Y2Ir2O7. By comparing the intensity of the "white-line"
features observed at the Ir L2 and L3 absorption edges, it is possible to
extract valuable information about the strength of the spin-orbit coupling in
these systems. We observe remarkably large, non-statistical branching ratios in
all Ir compounds studied, with little or no dependence on chemical composition,
crystal structure, or electronic state. This result confirms the presence of
strong spin-orbit coupling effects in novel iridates such as Sr2IrO4, Na2IrO3,
and Y2Ir2O7, and suggests that even simple Ir-based compounds such as IrO2 and
IrCl3 may warrant further study. In contrast, XAS measurements on Re-based 5d
compounds, such as Re, ReO2, ReO3, and Ba2FeReO6, reveal statistical branching
ratios and negligible spin-orbit coupling effects.

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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: comp-gas
2
The categories of this paper are: math
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The categories of this paper are: atom-ph
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The categories of this paper are: supr-con
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The categories of this paper are: quant-ph
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The categories of this paper are: plasm-ph
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The categories of this paper are: nucl-th
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The categories of this paper are: bayes-an
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The categories of this paper are: ao-sci
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The categories of this paper are: physics
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The categories of this paper are: eess
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The categories of this paper are: q-fin
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The categories of this paper are: nlin
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The categories of this paper are: chao-dyn