Dynamics ofF=2Spinor Bose-Einstein Condensates

Abstract

We experimentally investigate and analyze the rich dynamics in $F=2$ spinor Bose-Einstein condensates of ${}^{87}\mathrm{R}\mathrm{b}$. An interplay between mean-field driven spin dynamics and hyperfine-changing losses in addition to interactions with the thermal component is observed. In particular, we measure conversion rates in the range of ${10}^{-12}{\mathrm{c}\mathrm{m}}^3{\mathrm{s}}^{-1}$ for spin-changing collisions within the $F=2$ manifold and spin-dependent loss rates in the range of ${10}^{-13}{\mathrm{c}\mathrm{m}}^3{\mathrm{s}}^{-1}$ for hyperfine-changing collisions. We observe polar behavior in the $F=2$ ground state of ${}^{87}\mathrm{R}\mathrm{b}$, while we find the $F=1$ ground state to be ferromagnetic. We further see a magnetization for condensates prepared with nonzero total spin.