We have determined the scattering length of the ground state $^{7}\mathrm{Li}$ + $^{7}\mathrm{Li}$ singlet potential from spectroscopic data on the highest $S=0$ bound states. Combining this with a previously obtained triplet value we find the first example of an alkali atom hyperfine state (the $^{7}\mathrm{Li}$ $F=1$ , ${M}_{F}=\ensuremath{-}1$ state) for which the scattering length is positive. This implies a stable Bose condensate in future attempts to realize Bose-Einstein condensation in a magnetically trapped ultracold gas sample. We also predict magnetic-field-dependent resonances in the collision between atoms in the hyperfine state studied.We have determined the scattering length of the ground state $^{7}\mathrm{Li}$ + $^{7}\mathrm{Li}$ singlet potential from spectroscopic data on the highest $S=0$ bound states. Combining this with a previously obtained triplet value we find the first example of an alkali atom hyperfine state (the $^{7}\mathrm{Li}$ $F=1$, ${M}_{F}=\ensuremath{-}1$ state) for which the scattering length is positive. This implies a stable Bose condensate in future attempts to realize Bose-Einstein condensation in a magnetically trapped ultracold gas sample. We also predict magnetic-field-dependent resonances in the collision between atoms in the hyperfine state studied.

Physical Review LettersJul 25, 199464 citations

Stability of Magnetically Trapped Bose-Einstein Condensates

由紀川口, Yuki Kawaguchi

May 1, 20030 citations

Bose-Einstein Condensates in Magnetic Micro Traps

Claus Zimmermann, József Fortágh, Herwig Ott +2 more

International Conference on Atomic Physics (ICAP)Apr 1, 20031 citation

Condensate Formation in a Bose Gas

Henk T. C. Stoof

Using magnetically trapped atomic hydrogen as an example, we investigate the prospects of achieving Bose-Einstein condensation in a dilute Bose gas. We show that, if the gas is quenched sufficiently far into the critical region of the phase transition, the typical time scale for the nucleation of the condensate density is short and of $O(\hbar/k_{B}T_{c})$ . As a result we find that thermalizing elastic collisions act as a bottleneck for the formation of the condensate. In the case of doubly-polarized atomic hydrogen these occur much more frequently than the inelastic collisions leading to decay and we are lead to the conclusion that Bose-Einstein condensation can indeed be achieved within the lifetime of the gas.Using magnetically trapped atomic hydrogen as an example, we investigate the prospects of achieving Bose-Einstein condensation in a dilute Bose gas. We show that, if the gas is quenched sufficiently far into the critical region of the phase transition, the typical time scale for the nucleation of the condensate density is short and of $O(\hbar/k_{B}T_{c})$. As a result we find that thermalizing elastic collisions act as a bottleneck for the formation of the condensate. In the case of doubly-polarized atomic hydrogen these occur much more frequently than the inelastic collisions leading to decay and we are lead to the conclusion that Bose-Einstein condensation can indeed be achieved within the lifetime of the gas.

arXiv:cond-mat/9403010Mar 3, 19940 citations

Conditions for Bose-Einstein condensation in magnetically trapped atomic cesium

Eite Tiesinga, A. J. Moerdijk, BOUDEWIJN J. VERHAAR +1 more

We study conditions necessary for the observation of Bose-Einstein condensation in a magnetically trapped sample of atomic Cs gas. These conditions are associated with the value of the elastic scattering length, the rate of elastic scattering events, and the lifetime for decay of the density due to both magnetic dipole relaxation in two-body collisions, as well as recombination to ${\mathrm{Cs}}_{2}$ in three-body collisions. We find that, on the basis of these conditions, the prospects for observing Bose-Einstein condensation are favorable for a gas of ground-state Cs atoms in the highest state of the lowest hyperfine manifold. In all calculated elastic and inelastic two-body rates we find a pronounced resonance structure, which can be understood in terms of the interplay between the singlet-triplet interaction and the hyperfine, Zeeman, and magnetic dipole interactions. The experimental observation of these resonances may help to eliminate present uncertainties about interaction potentials.We study conditions necessary for the observation of Bose-Einstein condensation in a magnetically trapped sample of atomic Cs gas. These conditions are associated with the value of the elastic scattering length, the rate of elastic scattering events, and the lifetime for decay of the density due to both magnetic dipole relaxation in two-body collisions, as well as recombination to ${\mathrm{Cs}}_{2}$ in three-body collisions. We find that, on the basis of these conditions, the prospects for observing Bose-Einstein condensation are favorable for a gas of ground-state Cs atoms in the highest state of the lowest hyperfine manifold. In all calculated elastic and inelastic two-body rates we find a pronounced resonance structure, which can be understood in terms of the interplay between the singlet-triplet interaction and the hyperfine, Zeeman, and magnetic dipole interactions. The experimental observation of these resonances may help to eliminate present uncertainties about interaction potentials.

Physical Review AAug 1, 1992235 citations

We have determined the scattering length of the ground state

^{7}\mathrm{Li}

^{7}\mathrm{Li}

singlet potential from spectroscopic data on the highest

S=0

bound states. Combining this with a previously obtained triplet value we find the first example of an alkali atom hyperfine state (the

^{7}\mathrm{Li}

F=1

, ${M}_{F}=\ensuremath{-}1$ state) for which the scattering length is positive. This implies a stable Bose condensate in future attempts to realize Bose-Einstein condensation in a magnetically trapped ultracold gas sample. We also predict magnetic-field-dependent resonances in the collision between atoms in the hyperfine state studied.

O(\hbar/k_{B}T_{c})

. As a result we find that thermalizing elastic collisions act as a bottleneck for the formation of the condensate. In the case of doubly-polarized atomic hydrogen these occur much more frequently than the inelastic collisions leading to decay and we are lead to the conclusion that Bose-Einstein condensation can indeed be achieved within the lifetime of the gas.

{\mathrm{Cs}}_{2}

in three-body collisions. We find that, on the basis of these conditions, the prospects for observing Bose-Einstein condensation are favorable for a gas of ground-state Cs atoms in the highest state of the lowest hyperfine manifold. In all calculated elastic and inelastic two-body rates we find a pronounced resonance structure, which can be understood in terms of the interplay between the singlet-triplet interaction and the hyperfine, Zeeman, and magnetic dipole interactions. The experimental observation of these resonances may help to eliminate present uncertainties about interaction potentials.