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Scaling and self-averaging in the three-dimensional random-field Ising model

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 نشر من قبل Nikolaos Fytas G.
 تاريخ النشر 2010
  مجال البحث فيزياء
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We investigate, by means of extensive Monte Carlo simulations, the magnetic critical behavior of the three-dimensional bimodal random-field Ising model at the strong disorder regime. We present results in favor of the two-exponent scaling scenario, $bar{eta}=2eta$, where $eta$ and $bar{eta}$ are the critical exponents describing the power-law decay of the connected and disconnected correlation functions and we illustrate, using various finite-size measures and properly defined noise to signal ratios, the strong violation of self-averaging of the model in the ordered phase.

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