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Anomalous spin susceptibility and magnetic polaron formation in the double exchange systems

Hongsuk Yi·N. H. Hur·Jaejun Yu
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Abstract

The magnetic susceptibility and spin-spin correlation of the double-exchange model for doped manganites are investigated through the Monte Carlo calculations on the three-dimensional lattice model. Deviations of the susceptibility from the Curie-Weiss behavior above the ferromagnetic ordering temperature $T_c$ seem to indicate a formation of local ferromagnetic clusters in the vicinity of $T_c$, which is consistent with recent electron paramagnetic resonance experiments for La$_{2/3}$Ca$_{1/3}$MnO$_3$. A further analysis of the spin-spin correlations show the ferromagnetic cluster size to be three-to-four lattice spacings, suggesting that the charge carriers may form magnetic polarons.

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Hongsuk Yi, N. H. Hur, Jaejun Yu. 1999-10-11. Anomalous spin susceptibility and magnetic polaron formation in the double exchange systems. https://doi.org/10.1103/physrevb.61.9501

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