Optimal transitions between nonequilibrium steady states

Area of Science:

• Physics
• Physical Chemistry
• Statistical Mechanics

Background:

• Optimal control of microscale processes is crucial for energy-efficient nanomachines.
• Many real-world processes occur far from equilibrium, where memory effects are significant.
• Previous research focused on equilibrium transitions, leaving nonequilibrium regimes underexplored.

Purpose of the Study:

• To investigate optimal control strategies for finite-time transitions between nonequilibrium steady states (NESS).
• To explore the role of memory in optimal control within viscous and viscoelastic environments.
• To identify protocols minimizing thermodynamic work during NESS transitions.

Main Methods:

• Combined experimental, theoretical, and computational approaches.
• Studied the transition of a colloidal particle in an optical trap.
• Analyzed control protocols in different fluid environments (viscous and viscoelastic).

Main Results:

• Identified optimal control protocols that minimize thermodynamic work for NESS transitions.
• Demonstrated that optimal protocols balance energy extraction and dissipation minimization.
• Found that matching the environmental time response is crucial for optimal control in memory-laden systems.

Conclusions:

• Optimal control strategies are essential for efficient finite-time processes in complex, nonequilibrium environments.
• Memory effects significantly influence optimal control, requiring protocols to adapt to environmental dynamics.
• Findings provide insights for designing control strategies in nanomachines and biological systems.