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arXiv · 1308.6460

Slaving of the magnetic moment canting to the correlated oxygen rotation in Sr2IrO4 revealed by X-ray resonant scattering

S. Boseggia·H. C. Walker·J. Vale·R. Springell·Z. Feng·M. Moretti Sala·H. M. Rønnow·S. P. Collins·D. F. McMorrow
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Abstract

Sr2IrO4 is a prototype of the class of Mott insulators in the strong spin-orbit interaction (SOI) limit described by a $J_{\mathrm{eff}}=1/2$ ground state. In Sr2IrO4, the strong SOI is predicted to manifest itself in the slaving of the canting of the magnetic moments to the correlated rotation by 11.8(1)$^{\circ}$ of the oxygen octahedra that characterizes its distorted layered perovskite structure. Using X-ray resonant scattering at the Ir $L_3$ edge we have measured accurately the intensities of Bragg peaks arising from different components of the magnetic structure. From a careful comparison of integrated intensities of peaks due to basal-plane antiferromagnetism, with those due to b-axis ferromagnetism, we deduce a canting of the magnetic moments of 12.2(8)$^{\circ}$. We thus confirm that in Sr2IrO4 the magnetic moments rigidly follow the rotation of the oxygen octahedra, indicating that, even in the presence of significant non-cubic structural distortions, it is a close realization of the $J_{\mathrm{eff}}=1/2$ state

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S. Boseggia, H. C. Walker, J. Vale, R. Springell, Z. Feng, M. Moretti Sala, H. M. Rønnow, S. P. Collins, D. F. McMorrow. 2013-09-27. Slaving of the magnetic moment canting to the correlated oxygen rotation in Sr2IrO4 revealed by X-ray resonant scattering. https://doi.org/10.1088/0953-8984%2F25%2F42%2F422202

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