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Cooling an Optically Trapped Ultracold Fermi Gas by Periodical Driving
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Optimal Time-Entropy Bounds and Speed Limits for Brownian Thermal Shortcuts
Luís Barbosa Pires1, Rémi Goerlich1,2, Arthur Luna da Fonseca1,3
1University of Strasbourg and CNRS, CESQ and ISIS, UMR 7006, F-67000 Strasbourg, France.
Physical Review Letters
|September 18, 2023
Summary
Researchers engineered faster thermalization for optically trapped microspheres by controlling radiation pressure. This work establishes fundamental time-entropy limits for accelerated Brownian thermalization and optimized thermodynamic processes.
Area of Science:
- Thermodynamics
- Optics
- Statistical Mechanics
Background:
- Brownian motion and thermalization are fundamental in statistical mechanics.
- Controlling microscopic systems with light offers new avenues for thermodynamic manipulation.
- Understanding finite-time processes is crucial for optimizing real-world engines.
Purpose of the Study:
- To develop methods for accelerating thermal relaxation in optically trapped microspheres.
- To identify and quantify the entropic cost of accelerated thermal transfers.
- To establish fundamental limits on the speed of thermalization processes.
Main Methods:
- Real-time control of radiation pressure variance on an optically trapped microsphere.
- Engineering specific temperature protocols for accelerated state transfer.
- Deriving optimal protocols to minimize entropy production or maximize speed.
Main Results:
- Engineered temperature protocols that shortcut thermal relaxation.
- Identified the entropic footprint of accelerated transfers.
- Derived time-entropy bounds establishing speed limits for thermalization.
- Demonstrated acceleration of Brownian thermalization to fundamental limits.
Conclusions:
- Optimized finite-time thermodynamics for Brownian engines can be designed.
- The approach provides a platform for exploring information geometry and finite-time processes.
- Accelerated thermalization can be achieved by controlling radiation pressure and entropy.
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