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Nonequilibrium work fluctuations for oscillators in non-Markovian baths
1Department of Physics, University of California, Santa Cruz, California 95064, USA.
Summary
Work fluctuation theorems, including Jarzynski equality and Crooks
Area of Science:
- Thermodynamics
- Statistical Mechanics
- Non-equilibrium Physics
Background:
- Work fluctuation theorems are crucial for understanding non-equilibrium thermodynamics.
- Non-Markovian heat baths introduce memory effects, complicating theoretical analysis.
- Generalized Langevin equations describe systems coupled to complex environments.
Purpose of the Study:
- To investigate the validity of work fluctuation theorems for oscillators in non-Markovian heat baths.
- To determine the influence of bath memory on the exactness of these theorems.
- To explore the applicability of these theorems across different oscillator potentials and driving forces.
Main Methods:
- Analytical derivation of the work distribution function for a harmonic oscillator using the generalized Langevin equation.
- Numerical simulations for anharmonic oscillators to test theorem validity.
- Analysis of transient fluctuation theorem (TFT) under varying conditions.
Main Results:
- Jarzynski equality (JE), transient fluctuation theorem (TFT), and Crooks' theorem (CT) are shown to be exact for harmonic oscillators.
- Numerical simulations confirm that bath memory does not affect the validity of JE and CT for anharmonic oscillators.
- TFT is found to be inapplicable for asymmetric driving forces and potentials.
Conclusions:
- Work fluctuation theorems (JE, CT) are robust and hold for various oscillator types and driving protocols in non-Markovian environments.
- The transient fluctuation theorem has limitations concerning time- and position-asymmetric conditions.
- These findings advance the understanding of non-equilibrium statistical mechanics in complex systems.
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