Conversion of an Atomic Fermi Gas to a Long-Lived Molecular Bose Gas

Abstract

We have converted an ultracold Fermi gas of ${}^6$Li atoms into an ultracold gas of ${}^6$Li${}_2$ molecules by adiabatic passage through a Feshbach resonance. Approximately $1.5\times 10^5$ molecules in the least-bound, $v=38$, vibrational level of the X${}^1{\Sigma }_g^{+}$ singlet state are produced with an efficiency of 50%. The molecules remain confined in an optical trap for times of up to 1 s before we dissociate them by a reverse adiabatic sweep.

Accepted for publication in Phys. Rev. Letters