Robustness of Basal-Plane Antiferromagnetic Order and the Jeff=1/2 State in Single-Layer Iridate Spin-Orbit Mott Insulators

Henrik Moodysson Rønnow, Christian Rüegg
American Physical Society, 2013
Journal paper

Abstract

The magnetic structure and electronic ground state of the layered perovskite Ba2IrO4 have been investigated using x-ray resonant magnetic scattering. 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 ground state in Ba2IrO4, deduced from an investigation of the x-ray resonant magnetic scattering L3/L2 intensity ratio, is consistent with a Jeff=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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https://infoscience.epfl.ch/record/206255?ln=en

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