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arXiv · 1112.1799

Hourglass dispersion in overdoped single-layered manganites

H. Ulbrich·P. Steffens·D. Lamago·Y. Sidis·M. Braden
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Abstract

The excitation spectrum in single-layered Nd(0.33)Sr(1.67)MnO4 and Pr(0.33)Ca(1.67)MnO4 resembles the hourglass-like excitation dispersion seen in various cuprates superconductors. However, our spin-wave dispersion in Pr(0.33)Ca(1.67)MnO4, which exhibits a large correlation length of the magnetic order, showing outward-dispersing branches starting from the incommensurate zone-centres. The magnetic correlation length is identified as the decisive parameter to suppress this branches and generating an correct hourglass shape.

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H. Ulbrich, P. Steffens, D. Lamago, Y. Sidis, M. Braden. 2011-12-08. Hourglass dispersion in overdoped single-layered manganites. https://doi.org/10.1103/physrevlett.108.247209

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