title: Coherent optical transfer of Feshbach molecules to a lower vibrational state.
abstract: Using the technique of stimulated Raman adiabatic passage (STIRAP) we have coherently transferred ultracold (87)Rb(2) Feshbach molecules into a more deeply bound vibrational quantum level. Our measurements indicate a high transfer efficiency of up to 87%. Because the molecules are held in an optical lattice with not more than a single molecule per lattice site, inelastic collisions between the molecules are suppressed and we observe long molecular lifetimes of about 1 s. Using STIRAP we have created quantum superpositions of the two molecular states and tested their coherence interferometrically. These results represent an important step towards Bose-Einstein condensation of molecules in the vibrational ground state.
authors.affiliation: Institut für Experimentalphysik, Forschungszentrum für Quantenphysik, Universität Innsbruck, 6020 Innsbruck, Austria.
authors.forename: K
authors.initials: K
authors.lastname: Winkler
authors.forename: F
authors.initials: F
authors.lastname: Lang
authors.forename: G
authors.initials: G
authors.lastname: Thalhammer
authors.forename: P v d
authors.initials: Pv
authors.lastname: Straten
authors.forename: R
authors.initials: R
authors.lastname: Grimm
authors.forename: J Hecker
authors.initials: JH
authors.lastname: Denschlag