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Cooling an Optically Trapped Ultracold Fermi Gas by Periodical Driving
Published on: March 30, 2017
Conical intersections in an ultracold gas
S Wüster1, A Eisfeld, J M Rost
1Max Planck Institute for the Physics of Complex Systems, Nöthnitzer Strasse 38, 01187 Dresden, Germany.
Physical Review Letters
|May 17, 2011
Summary
Conical intersections (CIs) are common in multi-atom systems. We demonstrate how CIs influence excitation transport in a circular trimer, offering a new experimental probe of quantum dynamics.
Area of Science:
- Quantum Chemistry
- Atomic Physics
- Molecular Dynamics
Background:
- Conical intersections (CIs) are critical features in the potential energy surfaces of molecules, governing non-adiabatic dynamics.
- Transition dipole-dipole interactions are fundamental for understanding energy transfer in molecular systems.
Purpose of the Study:
- To investigate the generic occurrence and impact of conical intersections in multi-atom systems.
- To analyze the influence of CIs on adiabatic excitation transport in a circular trimer model.
- To propose an experimental setup for probing quantum dynamics near CIs.
Main Methods:
- Theoretical analysis of energy surfaces for systems with more than two atoms interacting via transition dipole-dipole potentials.
- Modeling adiabatic excitation transport in a circular trimer, considering electronic decoherence and geometric phase interference.
- Proposing an experimental realization using light alkali atoms in a ring trap with Rydberg state interactions.
Main Results:
- Energy surfaces of multi-atom systems interacting via transition dipole-dipole potentials generically exhibit conical intersections.
- Conical intersections significantly affect adiabatic excitation transport through electronic decoherence and geometric phase interference.
- A circular trimer model effectively demonstrates the impact of CIs on these transport mechanisms.
Conclusions:
- Conical intersections are a general feature impacting quantum dynamics in multi-atom systems.
- The proposed experimental setup with alkali atoms and Rydberg states offers a viable method to study many-body density dynamics near CIs.
- Understanding CI-mediated dynamics is crucial for controlling energy transfer in quantum systems.
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