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Dynamics of a colloidal particle driven by continuous time-delayed feedback.
Miranda C R Bell-Davies1,2, Arran Curran1,2, Yanyan Liu1
1Department of Chemistry, Physical and Theoretical Chemistry Laboratory, University of Oxford, South Parks Road, Oxford OX1 3QZ, United Kingdom.
Physical Review. E
|July 19, 2023
Summary
We studied colloidal dumbbell particle dynamics controlled by a delayed optical trap. A critical delay time transitions behavior from diffusive to driven, enabling stable motion and revealing thermodynamic insights.
Area of Science:
- Soft matter physics
- Statistical mechanics
- Non-equilibrium systems
Background:
- Colloidal particles are model systems for studying complex dynamics.
- Feedback control is crucial for manipulating microscopic systems.
- Active Brownian particle models describe self-propelled motion.
Purpose of the Study:
- To investigate the dynamics of a colloidal dumbbell particle under time-delayed feedback control.
- To identify the transition from diffusive to driven behavior.
- To analyze the stochastic thermodynamic properties of the system.
Main Methods:
- Experiments with colloidal dumbbell particles and repulsive optical traps.
- Simulations of particle dynamics under continuous-time-delayed feedback.
- Modeling using stochastic delay differential equations.
- Analysis of stochastic thermodynamic quantities.
Main Results:
- A transition from diffusive to driven dynamics was observed at a critical delay time.
- A condition for stable driven motion was derived.
- Maximum work done by the trap correlated with minimum mutual information.
- Onset of stable driven dynamics was linked to thermodynamic properties.
Conclusions:
- Time-delayed feedback can control colloidal particle dynamics, inducing a transition to driven behavior.
- Stochastic delay differential equations effectively model these systems.
- The interplay between feedback delay, particle dynamics, and thermodynamics is significant.
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