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Magnon softening and damping in the ferromagnetic manganites due to orbital correlations

S. Krivenko·A. Yaresko·G. Khaliullin·H. Fehske
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Abstract

We present a theory for spin excitations in ferromagnetic metallic manganites and demonstrate that orbital fluctuations have strong effects on the magnon dynamics in the case these compounds are close to a transition to an orbital ordered state. In particular we show that the scattering of the spin excitations by low-lying orbital modes with cubic symmetry causes both the magnon softening and damping observed experimentally.

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S. Krivenko, A. Yaresko, G. Khaliullin, H. Fehske. 2004-03-31. Magnon softening and damping in the ferromagnetic manganites due to orbital correlations. https://doi.org/10.1016/j.jmmm.2003.11.160

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