Barrier-controlled nonequilibrium criticality in reactive particle systems

Area of Science:

• Physics
• Chemical Dynamics
• Complex Systems

Background:

• Nonequilibrium critical phenomena are observed in dynamic systems like chemical reactions.
• Understanding phase transitions in driven-dissipative systems is crucial for various scientific fields.

Purpose of the Study:

• To investigate the role of the activation barrier in dynamic phase transitions.
• To explore criticality in a minimal reactive hard-sphere model.

Main Methods:

• Computer simulations were employed to model the system.
• Theoretical analysis, including mean-field theory and field simulation, was used.
• The study focused on a reactive hard-sphere model.

Main Results:

• The activation barrier's height dictates the type of dynamic phase transition.
• At zero thermal noise, increasing the activation barrier shifts the transition from continuous conserved directed percolation to discontinuous.
• A tricritical point governs this transition, and Ising-type criticality is possible at finite thermal noise.

Conclusions:

• The activation barrier is a key factor controlling nonequilibrium phase transitions.
• The findings provide a framework for understanding dynamic criticality in reactive systems.
• This research opens avenues for exploring complex behaviors in driven-dissipative systems.