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Physical meaning and measurement of the entropic parameter $q$ in an inhomogeneous magnetic systems

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

In this paper we present a thorough analysis of two systems magnetically inhomogeneous: the manganite La$_{0.7}$Sr$_{0.3}$MnO$_3$/MgO and the amorphous alloy Cu$_{90}$Co$_{10}$. In both cases, the non-extensive statistics yield a faithful description of the magnetic behavior of the systems. In the model proposed here, the inhomogeneous magnetic system is composed by many Maxwell-Boltzmann homogeneous bits and the entropic parameter $q$ is related to the moments of the distribution of the inhomogeneous quantity. From the analysis of Scanning Tunnelling Spectroscopy (STS) images, the $q$ parameter can be directly measured.

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M. S. Reis, V. S. Amaral, R. S. Sarthour, I. S. Oliveira. 2006-02-15. Physical meaning and measurement of the entropic parameter $q$ in an inhomogeneous magnetic systems. https://doi.org/10.1140/epjb%2Fe2006-00065-5

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