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Search for universal roughness distributions in a critical interface model

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 نشر من قبل Sergio L. A. de Queiroz
 تاريخ النشر 2004
  مجال البحث فيزياء
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 تأليف S.L.A. de Queiroz




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We study the probability distributions of interface roughness, sampled among successive equilibrium configurations of a single-interface model used for the description of Barkhausen noise in disordered magnets, in space dimensionalities $d=2$ and 3. The influence of a self-regulating (demagnetization) mechanism is investigated, and evidence is given to show that it is irrelevant, which implies that the model belongs to the Edwards-Wilkinson universality class. We attempt to fit our data to the class of roughness distributions associated to $1/f^alpha$ noise. Periodic, free, ``window, and mixed boundary conditions are examined, with rather distinct results as regards quality of fits to $1/f^alpha$ distributions.



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