arXiv:cond-mat/0301489

Comment on ``Ramsey Fringes in a Bose-Einstein Condensate between Atoms and Molecules''

Eric Braaten, H.‐W. Hammer, Masaoki Kusunoki

Published Jan 24, 2003• 1 citation

Abstract

In Phys. Rev. Lett. 89, 180401 (2002) [cond-mat/0204504], Kokkelmans and Holland interpret the results of a recent experiment at JILA that demonstrated atom-molecule coherence in a Bose-Einstein condensate. Using a mean-field approximation to a resonance field theory involving an atom condensate and a molecular condensate, they find that the molecular condensate is tiny compared to the atom condensate. We show that if the probability for the molecular field to create a diatomic molecule is correctly included, the numbers of atoms in the atom condensate and in the condensate of diatomic molecules are comparable.

DOI: 10.48550/arxiv.cond-mat/0301489

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arXiv:cond-mat/0301489

Comment on ``Ramsey Fringes in a Bose-Einstein Condensate between Atoms and Molecules''

Eric Braaten, H.‐W. Hammer, Masaoki Kusunoki

Published Jan 24, 2003• 1 citation

arXiv HTML PDF

Abstract

DOI: 10.48550/arxiv.cond-mat/0301489

Related papers

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arXiv:cond-mat/0204504Physical Review LettersOct 11, 2002147 citations

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Using the theoretical formalism of R A Duine and H T C Stoof (arXiv: cond-mat/0303230v) 22 March 2003), we have theoretically evaluated magnetic field and density dependence of the Josephson frequency in coherence atom-molecule oscillation in Bose-Einstein condensed gas.Our theoretically obtained results show that Josephson frequency increases with both magnetic field for constant condensate density and also with condensate density for fixed magnetic field.Our theoretically evaluated results are in good agreement with the experimental data and also with other theoretical workers.Using the theoretical formalism of Markes Greiner etal (Nature, 26 Nov (2005)) , we have studied the emergence of molecular Bose-Einstein condensate from a Fermi gas of 6 Li atoms.The study has been performed with the help of Feshbach resonance.We have evaluated molecular condensate fraction N0/N as a function of (T/TC) and as a function of (T/TF).We have also evaluated scattering length 'a' in unit of a0, of mixture of two lowest hyperfine states of 6 Li atom, temperature (µK) all as a function of magnetic field (mT) near the crossing of the An evaluation …Using the theoretical formalism of R A Duine and H T C Stoof (arXiv: cond-mat/0303230v) 22 March 2003), we have theoretically evaluated magnetic field and density dependence of the Josephson frequency in coherence atom-molecule oscillation in Bose-Einstein condensed gas.Our theoretically obtained results show that Josephson frequency increases with both magnetic field for constant condensate density and also with condensate density for fixed magnetic field.Our theoretically evaluated results are in good agreement with the experimental data and also with other theoretical workers.Using the theoretical formalism of Markes Greiner etal (Nature, 26 Nov (2005)) , we have studied the emergence of molecular Bose-Einstein condensate from a Fermi gas of 6 Li atoms.The study has been performed with the help of Feshbach resonance.We have evaluated molecular condensate fraction N0/N as a function of (T/TC) and as a function of (T/TF).We have also evaluated scattering length 'a' in unit of a0, of mixture of two lowest hyperfine states of 6 Li atom, temperature (µK) all as a function of magnetic field (mT) near the crossing of the An evaluation …

Journal of Chemical Biological and Physical SciencesJan 30, 20181 citation

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

^{85}\mathrm{Rb}

Bose-Einstein condensate was exposed to a sequence of magnetic field pulses on the high-field side of the

155\phantom{\rule{0.3em}{0ex}}\mathrm{G}

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.