Formation and detection of ultracold ground-state polar molecules

Abstract

We report on the formation of translationally cold NaCs molecules starting from a laser-cooled atomic vapor of Na and Cs atoms. Colliding atoms are transferred into bound molecular states in a two-step photoactivated process in which the atoms are first photoassociated by trap photons into an excited state molecular complex and then allowed to decay into a bound molecular ground state. Time-of-flight measurements show a translational temperature T = 260± 130 K that reflects the measured temperature of the initial atomic gas.

Formation of ultracold LiCs molecules

“…At the current state-of-the-art, heteronuclear alkali dimers seem to be particularly suited. Such ultracold polar dimers can be formed by photoassociation from ultracold samples of their atomic constituents as demonstrated for RbCs [21], KRb [14,22], and NaCs [23]. The dimer LiCs is predicted to have the largest dipole moment of about 5.5 Debye for low lying vibrational states of the X 1 Σ + ‡ Also at: Institut für Quantenoptik, Universität Hannover, Welfengarten 1, 30167 Hannover, Germany electronic ground state [16,17].…”

XΣ+1andaΣ+Staanum1, Pashov2, Knöckel3 et al. 2007Phys. Rev. A1199592View full textAdd to dashboardCite

“…Cold heteronuclear alkali dimers are subject to a large interest since they can be formed at temperatures below 1 mK [1,2,3,4,5] and possess a large permanent electric dipole moment for deeply bound singlet levels [6,7]. This combination of properties enables electric field control of ultracold collisions [8,9] and cold chemical reactions [10,11] and holds promises for applications in quantum computation [12].…”

Ultracold Heteronuclear Molecules and Ferroelectric Superfluids

“…Arguably one of the next frontiers in ultracold atomic and molecular physics is the study of two-species atomic mixtures [1,2,3,4,5,6], and ultracold heteronuclear molecules composed of two-species alkali atoms such as KRb [7,8,9], RbCs [10] and NaCs [11]. This frontier may be advanced through the use of Feshbach resonances which have already been observed in mixtures of twospecies alkali atoms [12,13,14], and may also become a crucial tool for tuning physical properties of heteronuclear systems.…”