Type: Article
Publication Date: 1998-12-07
Citations: 483
DOI: https://doi.org/10.1103/physrevlett.81.5109
A magnetic field-dependent Feshbach resonance has been observed in the elastic scattering collision rate between atoms in the $F\phantom{\rule{0ex}{0ex}}=\phantom{\rule{0ex}{0ex}}2,M\phantom{\rule{0ex}{0ex}}=\phantom{\rule{0ex}{0ex}}\ensuremath{-}2$ state of ${}^{85}\mathrm{Rb}$. Changing the magnetic field by several Gauss caused the collision rate to vary by a factor of 1${0}^{4}$, and the sign of the scattering length could be reversed. The resonance peak is at 155.2(4) G and its width is 11.6(5) G. From these results we extract much improved values for the three quantities that characterize the interaction potential: The van der Waals coefficient ${C}_{6}$, the singlet scattering length ${a}_{S}$, and the triplet scattering length ${a}_{T}$.