Dynamics of Janus motors with microscopically reversible kinetics

Area of Science:

• Chemical physics
• Statistical mechanics
• Soft matter physics

Background:

• Janus motors are micro-machines that require nonequilibrium conditions to operate.
• Detailed balance is typically broken by chemical fluxes, creating these nonequilibrium states.

Purpose of the Study:

• To develop a microscopic model for Janus motor reactive dynamics.
• To investigate Janus particle behavior in both equilibrium and nonequilibrium systems.
• To compare simulation results with fluctuating thermodynamics theory.

Main Methods:

• Constructed a microscopic model for reversible reactive collisions on Janus motor surfaces.
• Studied Janus particle reactive dynamics in equilibrium using generalized chemical rate laws.
• Drove the system into a nonequilibrium steady state using controlled chemical fluxes.
• Investigated statistical properties of self-propelled Janus motors.

Main Results:

• The microscopic model satisfies detailed balance under reversible reaction conditions.
• Generalized chemical rate laws with time-dependent coefficients describe reaction rates at equilibrium.
• The system reaches a nonequilibrium steady state controlled by chemical affinity.
• Statistical properties of the motor in the nonequilibrium state were analyzed.

Conclusions:

• The developed model provides a microscopic framework for studying Janus motors.
• It allows exploration of nonequilibrium fluctuations in self-diffusiophoretic motors.
• The findings contribute to understanding active matter and micro-machine dynamics.