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Non-Boltzmann stationary distributions and nonequilibrium relations in active baths
Aykut Argun1,2, Ali-Reza Moradi2,3,4, Erçaǧ Pinçe2
1Department of Physics, University of Gothenburg, SE-41296 Gothenburg, Sweden.
Physical Review. E
|January 14, 2017
Summary
Active baths cause non-equilibrium systems to deviate from classical thermodynamics. Researchers found that non-Boltzmann distributions emerge, but effective potentials can restore key thermodynamic relations.
Area of Science:
- Thermodynamics
- Statistical Mechanics
- Non-equilibrium Physics
Background:
- Many natural and engineered processes operate far from equilibrium.
- Classical equilibrium thermodynamics is insufficient for these systems.
- Active baths introduce non-equilibrium fluctuations.
Purpose of the Study:
- To experimentally investigate the impact of active bath fluctuations on thermodynamic quantities.
- To analyze how particle confinement affects stationary probability distributions.
- To explore the applicability and restoration of non-equilibrium relations.
Main Methods:
- Experimental study of a Brownian particle in a harmonic potential subjected to an active bath.
- Analysis of stationary probability distributions under varying confinement.
- Application of effective potential methods to restore thermodynamic relations.
Main Results:
- Stationary probability distribution transitions from Gaussian to heavy-tailed with increasing confinement.
- Non-Boltzmann distributions emerge, invalidating standard non-equilibrium relations.
- Restoration of Jarzynski equality and Crooks fluctuation theorem using effective potentials.
Conclusions:
- Active baths significantly alter thermodynamic behavior in confined systems.
- Effective potentials are crucial for accurately describing non-equilibrium systems.
- Experimental findings align with theoretical predictions, validating the approach.
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