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arXiv · 1502.00752

Probing single magnon excitations in Sr$_2$IrO$_4$ using O $K$-edge resonant inelastic X-ray scattering

X. Liu·M. P. M. Dean·J. Liu·S. G. Chiuzbăian·N. Jaouen·A. Nicolaou·W. G. Yin·C. Rayan Serrao·R. Ramesh·H. Ding·J. P. Hill
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Abstract

Resonant inelastic X-ray scattering (RIXS) at the $L$-edge of transition metal elements is now commonly used to probe single magnon excitations. Here we show that single magnon excitations can also be measured with RIXS at the $K$-edge of the surrounding ligand atoms when the center heavy metal elements have strong spin-orbit coupling. This is demonstrated with oxygen $K$-edge RIXS experiments on the perovskite Sr$_2$IrO$_4$, where low energy peaks from single magnon excitations were observed. This new application of RIXS has excellent potential to be applied to a wide range of magnetic systems based on heavy elements, for which the $L$-edge RIXS energy resolutions in the hard X-ray region is usually poor.

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X. Liu, M. P. M. Dean, J. Liu, S. G. Chiuzbăian, N. Jaouen, A. Nicolaou, W. G. Yin, C. Rayan Serrao, R. Ramesh, H. Ding, J. P. Hill. 2015-02-03. Probing single magnon excitations in Sr$_2$IrO$_4$ using O $K$-edge resonant inelastic X-ray scattering. https://doi.org/10.1088/0953-8984/27/20/202202

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