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Published on: May 30, 2014
Probabilistic Work Extraction on a Classical Oscillator Beyond the Second Law
Nicolas Barros1, Sergio Ciliberto1, Ludovic Bellon1
1<a href="https://ror.org/01rk35k63">Université de Lyon</a>, <a href="https://ror.org/04zmssz18">ENS de Lyon</a>, <a href="https://ror.org/02feahw73">CNRS</a>, <a href="https://ror.org/00w5ay796">Laboratoire de Physique</a>, F-69342 Lyon, France.
Researchers experimentally show that optimal protocols can enable system transitions with work less than free energy difference. The second law of thermodynamics holds on average, with fast protocols achieving over 95% probability for work less than free energy.
Area of Science:
- Thermodynamics
- Statistical Mechanics
- Non-equilibrium Physics
Background:
- The second law of thermodynamics traditionally states that work done must equal or exceed the free energy difference for a process.
- Understanding non-equilibrium processes is crucial for advancements in various scientific fields.
Purpose of the Study:
- To experimentally investigate the possibility of performing transitions between equilibrium states with work less than the free energy difference.
- To explore the conditions under which the second law of thermodynamics is satisfied on average.
Main Methods:
- Utilizing an underdamped oscillator in a double-well potential.
- Applying optimal protocols to drive the system between two equilibrium states.
- Analyzing experimental trajectories to quantify work done and free energy difference.
Main Results:
- Demonstrated that applying optimal protocols can maximize the probability of transitions with work (W) less than the free energy difference (ΔF).
- Achieved over 95% probability for trajectories where W ≤ ΔF under specific parameter choices.
- Confirmed that the second law of thermodynamics holds on average, expressed as ⟨W⟩ ≥ ΔF.
Conclusions:
- Experimental evidence supports the Jarzynski equality in explaining non-equilibrium thermodynamic processes.
- Fast protocols are essential for achieving significant probabilities of work values below the free energy difference.
- This research offers insights into the statistical nature of the second law in driven systems.
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