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Updated: May 30, 2026
11:21
Cooling an Optically Trapped Ultracold Fermi Gas by Periodical Driving
Published on: March 30, 2017
Deeply bound cold caesium molecules formed after 0(-)(g) resonant coupling.
H Lignier1, A Fioretti, R Horchani
1Laboratoire Aimé Cotton, CNRS, Univ. Paris Sud, bât. 505, Campus d'Orsay, 91405, Orsay Cedex, France. andrea.fioretti@lac.u-psud.fr.
Physical Chemistry Chemical Physics : PCCP
|August 5, 2011
Summary
Cold caesium molecules were created and studied. Resonant coupling significantly altered their energy levels and decay pathways, offering new possibilities for cold molecule manipulation.
Area of Science:
- Atomic and Molecular Physics
- Quantum Chemistry
- Spectroscopy
Background:
- Cold molecules are crucial for precision measurements and quantum simulations.
- Photoassociation is a key technique for creating ultracold molecules.
Purpose of the Study:
- To investigate the properties of translationally cold caesium molecules.
- To understand the effects of resonant coupling on molecular energy levels and decay dynamics.
Main Methods:
- Creation of cold caesium molecules via photoassociation.
- Selective detection using resonance-enhanced two-photon ionization (RE2PI).
- Analysis of vibrational spacings and rotational constants.
- Theoretical modeling and quantum defect analysis.
Main Results:
- Identification of excited vibrational levels in the 0⁻(g) symmetry state.
- Observation of deviations in vibrational and rotational structures due to resonant coupling.
- Coupling with states dissociating to 6s + 6p(3/2) and 6s + 5d(3/2) asymptotes.
- Dramatic changes in spontaneous decay products, enhancing population transfer to triplet and ground states.
Conclusions:
- Resonant coupling significantly perturbs cold caesium molecule energy levels.
- This coupling influences molecular decay pathways, enhancing population transfer.
- Findings are relevant for developing population transfer schemes in cold molecule systems.
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