arXiv:1411.0263 · Physical Review E

Universal free-energy distribution in the critical point of a random Ising ferromagnet

Victor S Dotsenko, Yurij V. Holovatch

Published Nov 14, 2014• 3 citations

Abstract

We discuss the non-self-averaging phenomena in the critical point of weakly disordered Ising ferromagnet. In terms of the renormalized replica Ginzburg-Landau Hamiltonian in dimensions D<4, we derive an explicit expression for the probability distribution function (PDF) of the critical free-energy fluctuations. In particular, using known fixed-point values for the renormalized coupling parameters, we obtain the universal curve for such PDF in the dimension D=3. It is demonstrated that this function is strongly asymmetric: its left tail is much slower than the right one.

DOI: 10.1103/physreve.90.052126

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