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Experimental determination of the non-extensive entropic parameter $q$

M. S. Reis·V. S. Amaral·R. S. Sarthour·I. S. Oliveira
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Abstract

We show how to extract the $q$ parameter from experimental data, considering an inhomogeneous magnetic system composed by many Maxwell-Boltzmann homogeneous parts, which after integration over the whole system recover the Tsallis non-extensivity. Analyzing the cluster distribution of La$_{0.7}$Sr$_{0.3}$MnO$_{3}$ manganite, obtained through scanning tunnelling spectroscopy, we measure the $q$ parameter and predict the bulk magnetization with good accuracy. The connection between the Griffiths phase and non-extensivity is also considered. We conclude that the entropic parameter embodies information about the dynamics, the key role to describe complex systems.

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M. S. Reis, V. S. Amaral, R. S. Sarthour, I. S. Oliveira. 2005-12-09. Experimental determination of the non-extensive entropic parameter $q$. https://doi.org/10.1103/physrevb.73.092401

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