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Cooling an Optically Trapped Ultracold Fermi Gas by Periodical Driving
Published on: March 30, 2017
Ultracold bosons in a tilted multilevel double-well potential
D R Dounas-Frazer1, A M Hermundstad, L D Carr
1Department of Physics, Colorado School of Mines, Golden, Colorado 80401, USA.
Physical Review Letters
|February 1, 2008
Summary
Creating macroscopic quantum superposition in ultracold atoms requires more than just the ground state. Two energy levels are often necessary, but a small tilt can destroy these states, though interactions can partially restore them.
Area of Science:
- Quantum physics
- Atomic physics
- Many-body systems
Background:
- Macroscopic quantum superposition is crucial for ultracold atom experiments.
- The standard approach often relies on single-particle ground states within potential wells.
- The N-body problem in tilted double wells presents unique challenges.
Purpose of the Study:
- To determine the conditions under which multiple energy levels are necessary for describing quantum states in a tilted double-well potential.
- To investigate the feasibility of creating macroscopic superposition states in such systems.
- To analyze the impact of external tilts and atom-atom interactions on these superposition states.
Main Methods:
- Theoretical analysis of the N-body problem within a tilted double-well potential.
- Derivation of criteria for the number of energy levels required to characterize the system's state space.
- Simulation of ultracold atom behavior under varying tilt angles and interaction strengths.
Main Results:
- Explicit criteria are provided for when two energy levels are essential for state description.
- For typical experimental parameters, two energy levels are indeed required for macroscopic superposition.
- A small external tilt leads to the collapse of these macroscopic superposition states.
- Partial recovery of macroscopic superposition states is observed when atom-atom interactions compensate for the tilt.
Conclusions:
- The creation of macroscopic quantum superposition in tilted double wells necessitates a departure from single-level approximations.
- System parameters and external fields critically influence the stability of superposition states.
- Atom-atom interactions offer a potential mechanism to stabilize superposition states against external perturbations.
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