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arXiv · 2305.12161

Superdiffusion-like behavior in zero-temperature coarsening of the $d=3$ Ising model

Abstract

One key aspect of coarsening following a quench below the critical temperature is domain growth. For the non-conserved Ising model a power-law growth of domains of like spins with exponent $α= 1/2$ is predicted. Including recent work, it was not possible to clearly observe this growth law in the special case of a zero-temperature quench in the three-dimensional model. Instead a slower growth with $α<1/2$ was reported. We attempt to clarify this discrepancy by running large-scale Monte Carlo simulations of lattice sizes up to $L=2048$ employing an efficient GPU implementation. Indeed, at late times we measure domain sizes compatible with the expected growth law -- but surprisingly, at still later times domains even grow superdiffusively, i.e., with $α> 1/2$. We argue that this new problem is possibly caused by sponge-like structures emerging at early times.

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Denis Gessert, Henrik Christiansen, Wolfhard Janke. 2023-05-20. Superdiffusion-like behavior in zero-temperature coarsening of the $d=3$ Ising model. https://doi.org/10.1038/s41598-023-39328-7

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