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arXiv · 0801.1787

Melting of magnetic correlations in charge-orbital ordered La(0.5)Sr(1.5)MnO(4) : competition of ferro and antiferromagnetic states

D. Senff·O. Schumann·M. Benomar·M. Kriener·T. Lorenz·Y. Sidis·K. Habicht·P. Link·M. Braden
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Abstract

The magnetic correlations in the charge- and orbital-ordered manganite La(0.5)Sr(1.5)MnO(4) have been studied by elastic and inelastic neutron scattering techniques. Out of the well-defined CE-type magnetic structure with the corresponding magnons a competition between CE-type and ferromagnetic fluctuations develops. Whereas ferromagnetic correlations are fully suppressed by the static CE-type order at low temperature, elastic and inelastic CE-type correlations disappear with the melting of the charge-orbital order at high temperature. In its charge-orbital disordered phase, La(0.5)Sr(1.5)MnO(4) exhibits a dispersion of ferromagnetic correlations which remarkably resembles the magnon dispersion in ferromagnetically ordered metallic perovskite manganites.

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D. Senff, O. Schumann, M. Benomar, M. Kriener, T. Lorenz, Y. Sidis, K. Habicht, P. Link, M. Braden. 2008-01-11. Melting of magnetic correlations in charge-orbital ordered La(0.5)Sr(1.5)MnO(4) : competition of ferro and antiferromagnetic states. https://doi.org/10.1103/physrevb.77.184413

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