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Updated: May 2, 2026
11:21
Cooling an Optically Trapped Ultracold Fermi Gas by Periodical Driving
Published on: March 30, 2017
7.1K
Tunable Fermi acceleration in a nondissipative driven magnetic billiard.
B Castaldi1, R Egydio de Carvalho1, C Vieira Abud2
1Universidade Estadual Paulista-UNESP, Rio Claro-SP, Brazil.
Summary
A constant magnetic field can deactivate Fermi acceleration (FA) in a nondissipative annular billiard system. Particle trajectory curving by the magnetic field suppresses FA, even without dissipation.
Area of Science:
- Physics
- Nonlinear Dynamics
- Statistical Mechanics
Background:
- Fermi acceleration (FA) is a mechanism for particle energization.
- The annular billiard model with breathing boundaries is a system where FA can occur.
- Understanding factors influencing FA is crucial for various physical phenomena.
Purpose of the Study:
- To investigate the effect of a constant magnetic field on Fermi acceleration.
- To determine if and how a magnetic field can suppress FA in this system.
- To identify potential thresholds for FA deactivation.
Main Methods:
- Theoretical analysis of particle dynamics in a nondissipative annular billiard.
- Inclusion of a constant external magnetic field.
- Examination of particle trajectories under varying magnetic field strengths and system parameters.
Main Results:
- A critical magnetic field threshold was identified.
- Above this threshold, the magnetic field deactivates Fermi acceleration.
- Particle trajectory curvature induced by the magnetic field leads to non-trivial suppression of FA without dissipation.
Conclusions:
- Constant magnetic fields can effectively suppress Fermi acceleration in specific nondissipative systems.
- The suppression is dependent on the magnetic field strength and system parameters.
- This finding offers insights into controlling particle energization mechanisms.
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