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arXiv · 1210.6634

Strongly momentum-dependent screening dynamics in La$_{0.5}$Sr$_{1.5}$MnO$_4$ observed with resonant inelastic x-ray scattering

X. Liu·T. F. Seman·K. H. Ahn·Michel van Veenendaal·D. Casa·D. Prabhakaran·A. T. Boothroyd·H. Ding·J. P. Hill
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Abstract

We report strongly momentum-dependent local charge screening dynamics in CE-type charge, orbital, and spin ordered La$_{0.5}$Sr$_{1.5}$MnO$_4$, based on Mn K-edge resonant inelastic x-ray scattering data. Through a comparison with theoretical calculations, we show that the observed momentum dependence reflects highly localized, nearest neighbor screening of the transient local charge perturbation in this compound with an exciton-like screening cloud, rather than delocalized screening. The size of the screening cloud is estmated to be about 0.4-0.5 interatomic distances.

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X. Liu, T. F. Seman, K. H. Ahn, Michel van Veenendaal, D. Casa, D. Prabhakaran, A. T. Boothroyd, H. Ding, J. P. Hill. 2012-10-24. Strongly momentum-dependent screening dynamics in La$_{0.5}$Sr$_{1.5}$MnO$_4$ observed with resonant inelastic x-ray scattering. https://doi.org/10.1103/physrevb.87.201103

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