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Updated: May 18, 2026
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Cooling an Optically Trapped Ultracold Fermi Gas by Periodical Driving
Published on: March 30, 2017
Zon-Cohen singularity and negative inverse temperature in a trapped-particle limit
1Department of Basic Science, The University of Tokyo, Tokyo, 153-8902, Japan.
Physical Review. E, Statistical, Nonlinear, and Soft Matter Physics
|September 26, 2012
Summary
We analyzed a Brownian particle
Area of Science:
- Statistical mechanics
- Non-equilibrium thermodynamics
Background:
- Brownian motion is fundamental to understanding particle dynamics.
- Fluctuation theorems describe statistical properties in non-equilibrium systems.
Purpose of the Study:
- Investigate work and heat dissipation for a Brownian particle in a moving periodic potential.
- Analyze statistical properties under specific potential conditions.
Main Methods:
- Boundary layer analysis was employed for large potential periods and depths.
- Calculated the cumulant generating function and biased distribution function.
Main Results:
- Derived key statistical properties of work and heat.
- Identified a Zon-Cohen singularity in an extended fluctuation theorem.
Conclusions:
- The study provides insights into rare trajectories and negative inverse temperature.
- Offers a new perspective on fluctuation theorems in non-equilibrium statistical mechanics.
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