2004/07/31 by Krzysztof Goral, Krzysztof Góral, Thorsten Koehler +3 · 2 citations
Chemistry · Physics and Astronomy · #Cold Atom Physics and Bose-Einstein Condensates #Spectroscopy and Laser Applications #Strong Light-Matter Interactions #cond-mat.other #physics.atom-ph #quant-ph
paper · pdf · doi:10.1103/physreva.71.023603
published as Phys. Rev. A 71, 023603 (2005) · 22 pages, 12 eps figures; final version
openalex publication_date 2005/02/09 · arxiv created 2005/02/10 · arxiv updated 2009/12/01 · openalex created_date 2016/06/24 · openalex updated_date 2026/07/30
We discuss the frequency and visibility of atom-molecule Ramsey fringes observed in recent experiments by Claussen et al. [Phys. Rev. A 67, 060701 (2003)]. In these experiments a 85Rb Bose-Einstein condensate was exposed to a sequence of magnetic field pulses on the high-field side of the 155\phantom\rule0.3em0exG Feshbach resonance. The observed oscillation frequencies largely agree with the theoretically predicted magnetic field dependence of the binding energy of the highest excited diatomic vibrational state, except for a small region very close to the singularity of the scattering length. Our analytic treatment of the experiment, as well as our dynamical simulations, follow the magnitude of the measured oscillation frequencies as well as the visibilities of the Ramsey fringes. We show that significant deviations from a purely binary dynamics, with an associated binding frequency, occur when the spatial extent of the molecular wave function becomes comparable with the mean distance between the atoms in the dilute gas. The experiments thus clearly identify the conditions under which diatomic molecules may be identified as a separate entity of the gas or, conversely, when the concept of binary physics in a many-body environment is bound to break down.