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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
Condensed Matter

Abstract.

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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Copyright information

© EDP Sciences/Società Italiana di Fisica/Springer-Verlag 2006

Authors and Affiliations

  • M. S. Reis
    • 1
  • V. S. Amaral
    • 1
  • R. S. Sarthour
    • 2
  • I. S. Oliveira
    • 2
  1. 1.Departamento de Física and CICECOUniversidade de AveiroAveiroPortugal
  2. 2.Centro Brasileiro de Pesquisas Físicas, Rua Dr. Xavier Sigaud 150 UrcaRio de Janeiro-RJBrasil

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