Barrier-Controlled Non-Equilibrium Criticality in Reactive Particle Systems

Qun-Li Lei; Hao Hu; Ran Ni

doi:10.1103/physreve.103.052607

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arXiv · 2006.08075

Barrier-Controlled Non-Equilibrium Criticality in Reactive Particle Systems

Qun-Li Lei·Hao Hu·Ran Ni

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Abstract

Non-equilibrium critical phenomena generally exist in many dynamic systems, like chemical reactions and some driven-dissipative {reactive} particle systems. Here, by using computer simulation and theoretical analysis, we demonstrate the crucial role of the activation barrier on the criticality of dynamic phase transitions in a minimal reactive hard-sphere model. We find that at zero thermal noise, with increasing the activation barrier, the type of transition changes from a continuous conserved directed percolation into a discontinuous dynamic transition by crossing a \emph{tricritical} point. A mean-field theory combined with field-simulation is proposed to explain this phenomenon. The possibility of Ising-type criticality in the non-equilibrium system at finite thermal noise is also discussed.

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Qun-Li Lei, Hao Hu, Ran Ni. 2020-06-15. Barrier-Controlled Non-Equilibrium Criticality in Reactive Particle Systems. https://doi.org/10.1103/physreve.103.052607

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