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Surface criticality in random field magnets

L. Laurson·M. J. Alava
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Abstract

The boundary-induced scaling of three-dimensional random field Ising magnets is investigated close to the bulk critical point by exact combinatorial optimization methods. We measure several exponents describing surface criticality: $β_1$ for the surface layer magnetization and the surface excess exponents for the magnetization and the specific heat, $β_s$ and $α_s$. The latter ones are related to the bulk phase transition by the same scaling laws as in pure systems, but only with the same violation of hyperscaling exponent $θ$ as in the bulk. The boundary disorders faster than the bulk, and the experimental and theoretical implications are discussed.

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L. Laurson, M. J. Alava. 2005-10-27. Surface criticality in random field magnets. https://doi.org/10.1103/physrevb.72.214416

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