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arXiv · 2008.02329

A particle-based Ising model

Quentin Novinger·Antonio Suma·Daniel Sigg·Giuseppe Gonnella·Vincenzo Carnevale
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Abstract

We characterize equilibrium properties and relaxation dynamics of a two-dimensional lattice containing, at each site, two particles connected by a double-well potential (dumbbell). Dumbbells are oriented in the orthogonal direction with respect to the lattice plane and interact with each other through a Lennard-Jones potential truncated at the nearest neighbor distance. We show that the system's equilibrium properties are accurately described by a two-dimensional Ising model with an appropriate coupling constant. Moreover, we characterize the coarsening kinetics by calculating the cluster size as a function of time and compare the results with Monte Carlo simulations based on Glauber or reactive dynamics rate constants.

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Quentin Novinger, Antonio Suma, Daniel Sigg, Giuseppe Gonnella, Vincenzo Carnevale. 2020-08-05. A particle-based Ising model. https://doi.org/10.1103/physreve.103.012125

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