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arXiv · 1205.6540

Spin-Orbit Coupling in Iridium-Based 5d Compounds Probed by X-ray Absorption Spectroscopy

J. P. Clancy·N. Chen·C. Y. Kim·W. F. Chen·K. W. Plumb·B. C. Jeon·T. W. Noh·Young-June Kim
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Abstract

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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J. P. Clancy, N. Chen, C. Y. Kim, W. F. Chen, K. W. Plumb, B. C. Jeon, T. W. Noh, Young-June Kim. 2012-05-30. Spin-Orbit Coupling in Iridium-Based 5d Compounds Probed by X-ray Absorption Spectroscopy. https://doi.org/10.1103/physrevb.86.195131

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