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arXiv · 2202.13895

Suppression of discontinuous phase transitions by particle diffusion

Chul-Ung Woo·Heiko Rieger·Jae Dong Noh
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Abstract

We investigate the phase transitions of the $q$-state Brownian Potts model in two dimensions (2d) comprising Potts spins that diffuse like Brownian particles and interact ferromagnetically with other spins within a fixed distance. With extensive Monte Carlo simulations we find a continuous phase transition from a paramagnetic to a ferromagnetic phase even for $q>4$. This is in sharp contrast to the existence of a discontinuous phase transition in the equilibrium $q$-state Potts model in 2d with $q>4$. We present detailed numerical evidence for a continuous phase transition and argue that diffusion generated dynamical positional disorder suppresses phase coexistence leading to a continuous transition.

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Chul-Ung Woo, Heiko Rieger, Jae Dong Noh. 2022-02-28. Suppression of discontinuous phase transitions by particle diffusion. https://doi.org/10.1103/physreve.105.054144

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