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arXiv · 1108.4523

Resonant X-Ray Diffraction Study of Strongly Spin-Orbit-Coupled Mott Insulator CaIrO3

Kenya Ohgushi·Jun-ichi Yamaura·Hiroyuki Ohsumi·Kunihisa Sugimoto·Soshi Takeshita·Akihisa Tokuda·Hidenori Takagi·Masaki Takata·Taka-hisa Arima
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Abstract

We performed resonant x-ray diffraction experiments at the $L$ absorption edges for the post-perovskite-type compound CaIrO$_{3}$ with $(t_{2g})^5$ electronic configuration. By observing the magnetic signals, we could clearly see that the magnetic structure was a striped order with an antiferromagnetic moment along the c-axis and that the wavefunction of a $t_{2g}$ hole is strongly spin-orbit entangled, the $J_{\rm eff} =1/2$ state. The observed spin arrangement is consistent with theoretical work predicting a unique superexchange interaction in the $J_{\rm eff} =1/2$ state and points to the universal importance of the spin-orbit coupling in Ir oxides, irrespective of the local coordination and lattice topology. We also propose that the non-magnetic resonant scattering is a powerful tool for unraveling an orbital state even in a metallic iridate.

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Kenya Ohgushi, Jun-ichi Yamaura, Hiroyuki Ohsumi, Kunihisa Sugimoto, Soshi Takeshita, Akihisa Tokuda, Hidenori Takagi, Masaki Takata, Taka-hisa Arima. 2011-08-23. Resonant X-Ray Diffraction Study of Strongly Spin-Orbit-Coupled Mott Insulator CaIrO3. https://arxiv.org/abs/1108.4523

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