Physical meaning and measurement of the entropic parameter q in an inhomogeneous magnetic systems
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In this paper we present a thorough analysis of two systems magnetically inhomogeneous: the manganite La0.7Sr0.3MnO3/MgO and the amorphous alloy Cu90Co10. 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.
PACS.05.70.Ce Thermodynamic functions and equations of state 05.70.Fh Phase transitions: general studies
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