Nonequilibrium phase transition in a driven Potts model with friction

Area of Science:

• Condensed Matter Physics
• Statistical Mechanics
• Non-equilibrium Systems

Background:

• Investigates magnetic friction between two interacting systems of q-state Potts spins.
• Considers systems moving at a relative constant velocity (ν), creating a steady state far from equilibrium.
• Highlights the permanent energy flow due to surface spin interactions.

Purpose of the Study:

• To analytically and computationally study nonequilibrium phase transitions in driven magnetic spin systems.
• To explore the dependence of these transitions on system parameters like velocity (ν) and spin states (q).
• To characterize the nature of these exotic transitions, particularly in relation to equilibrium phase transitions.

Main Methods:

• Analytical treatment in the limit of infinite velocity (ν=∞) in 1D and for large q values in 2D.
• Monte Carlo simulations in 2D for finite velocity (ν) and finite q values.
• Analysis of energy flow and phase transition properties.

Main Results:

• Exotic nonequilibrium phase transitions were observed.
• The properties of these transitions are directly linked to the type of equilibrium phase transition.
• When the equilibrium transition is first-order, a sequence of second- and first-order nonequilibrium transitions occurs as interaction strength varies.

Conclusions:

• Driven magnetic spin systems exhibit complex nonequilibrium phase transitions.
• The behavior of these nonequilibrium transitions is governed by the underlying equilibrium phase diagram.
• This work provides insights into the physics of systems operating far from thermal equilibrium.