Coarsening and percolation in a disordered ferromagnet.

Phys Rev E

Laboratoire de Physique Théorique et Hautes Energies, Université Pierre et Marie Curie, Sorbonne Universités, 4 Place Jussieu, 75252 Paris Cedex 05, France.

Published: February 2017

By studying numerically the phase-ordering kinetics of a two-dimensional ferromagnetic Ising model with quenched disorder (either random bonds or random fields) we show that a critical percolation structure forms at an early stage. This structure is then rendered more and more compact by the ensuing coarsening process. Our results are compared to the nondisordered case, where a similar phenomenon is observed, and they are interpreted within a dynamical scaling framework.

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http://dx.doi.org/10.1103/PhysRevE.95.022101DOI Listing

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