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arXiv · 1212.5912

Robustness of basal-plane antiferromagnetic order and the $J_{eff}=1/2$ state in single-layer iridate spin-orbit Mott insulators

S. Boseggia·R. Springell·H. C. Walker·Ch. Rüegg·H. Okabe·M. Isobe·R. S. Perry·S. P. Collins·D. F. McMorrow
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Abstract

The magnetic structure and electronic groundstate of the layered perovskite Ba2IrO4 have been investigated using x-ray resonant magnetic scattering (XRMS). Our results are compared with those for Sr2IrO4, for which we provide supplementary data on its magnetic structure. We find that the dominant, long-range antiferromagnetic order is remarkably similar in the two compounds, and that the electronic groundstate in Ba2IrO4, deduced from an investigation of the XRMS $L_3/L_2$ intensity ratio, is consistent with a $J_{eff}=1/2$ description. The robustness of these two key electronic properties to the considerable structural differences between the Ba and Sr analogues is discussed in terms of the enhanced role of the spin-orbit interaction in 5d transition metal oxides.

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S. Boseggia, R. Springell, H. C. Walker, Ch. Rüegg, H. Okabe, M. Isobe, R. S. Perry, S. P. Collins, D. F. McMorrow. 2012-12-24. Robustness of basal-plane antiferromagnetic order and the $J_{eff}=1/2$ state in single-layer iridate spin-orbit Mott insulators. https://doi.org/10.1103/physrevlett.110.117207

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