Coherent two-photon photoassociation of a quantum degenerate gas of ^7Li
Abstract
We perform photoassociative spectroscopy on magnetically trapped, quantum degenerate ^7Li atoms at temperatures below 300 nK. Two co-propagating phase locked lasers, each tuned near the v' = 72 vibrational level in the excited state, drive a two-photon Raman transition to the v'' = 10 vibrational level of the 1^3Σ_u^+ state. Spectral features as narrow as 200 Hz are observed. The observed Wigner threshold lineshapes reflect the thermal energy distribution of the gas. At higher intensities, coherent effects are evident even though only a small fraction of atoms are Bose condensed. In particular, dispersive features, whose parity depends on the sign of the detuning from the intermediate state, are observed as well as the Autler-Townes effect. These results suggest that methods of coherent population transfer may be effective for producing ultracold, trappable molecules by photoassociation of a non-Bose condensed gas.
- Publication:
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APS Division of Atomic, Molecular and Optical Physics Meeting Abstracts
- Pub Date:
- May 2002
- Bibcode:
- 2002APS..DMP.C2003J