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Magnetic behavior of a non-extensive S-spin system: possible connections to manganites

M. S. Reis·J. P. Araujo·V. S. Amaral·E. K. Lenzi·I. S. Oliveira
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Abstract

We analyzed the magnetic behavior of a S-spin system within framework of the Tsallis nonextensive statistics, employing the normalized approach. Unusual properties on magnetization, entropy and susceptibility emerge, as a consequence of nonextensivity. We further show that the nonextensive approach can be relevant to the field of manganites, materials which exhibit long-range interactions and fractality, two basic ingredients for nonextensivity. Our results are in qualitative agreement to experimental data in La$_{0.67}$Ca$_{0.33}$MnO$_3$ and Pr$_{0.5}$Ca$_{0.5}$Mn$_{0.95}$Ga$_{0.05}$O$_3$ manganites.

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M. S. Reis, J. P. Araujo, V. S. Amaral, E. K. Lenzi, I. S. Oliveira. 2002-07-09. Magnetic behavior of a non-extensive S-spin system: possible connections to manganites. https://doi.org/10.1103/physrevb.66.134417

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