Rice Group Publishes Paper in Physical Review

Randy Hulet of Rice University reports that the following paper has been accepted for publication in Physical Review A: "Photoassociative Frequency Shift in a Quantum Degenerate Gas", by J. M. Gerton, B. J. Frew, and R. G. Hulet

The authors describe their observations of a light-induced frequency shift in the single-photon photoassociative spectra of magnetically trapped, quantum degenerate Li-7. The shift is a manifestation of the coupling between the threshold continuum scattering states and discrete bound levels in the excited-state molecular potential induced by the photoassociation laser. The frequency shift is observed to be linear in the laser intensity with a measured proportionality constant that is in good agreement with theoretical predictions. The frequency shift has important implications for a scheme to alter the interactions between atoms in a Bose-Einstein condensate using photoassociation resonances.