Optical traps for quantum gases

Cold inelastic collisions between lithium and cesium in a two-species magneto-optical trap

“…Such mixtures open new perspectives for collisional studies in conservative potentials like magnetic or optical traps, for the formation and trapping of cold polar molecules through, e.g., photoassociation, or for the investigation of two-species Bose condensates [28]. Starting from our two-species MOT, we plan to transfer the cold lithium and cesium simultaneously into a far-detuned optical dipole trap [29] for the investigation of elastic Li-Cs collisions with the prospect to sympathetically cool lithium with optically cooled cesium [14].…”

“…the lightest and the heaviest stable alkali. This extreme combination opens intriguing perspectives for future experiments related to the large difference in mass and electron affinity of the two atomic species, e.g., sympathetic cooling of lithium by optically cooled cesium [14] and the formation of cold polar molecules with large electric dipole moment which could be trapped electrostatically [15]. In our experiments, both species are simultaneously confined in a combined magneto-optical trap.…”

Optical Dipole Traps for Neutral Atoms

“…This is why, until now, only one experiment is reported on evaporative cooling in dipole traps starting with a small sample of atoms (Adams et al, 1995). By precooling large ensembles in dipole traps with optical methods explained in the preceeding paragraphs, much better starting conditions for evaporative cooling are achievable (Engler et al, 1998;Vuletic et al, 1998;Winoto et al, 1998) making evaporative cooling a still interesting option for future applications.…”

“…The GOST offers several interesting options for future experiments on dense atomic gases (Engler et al, 1998). By detuning the EW and the hollow beam very far from resonance, a situation can be reached in which the photon scattering rate is far below 1 s −1 .…”

Efimov States in an Ultracold Gas: How it Happened in the Laboratory

“…In an optical dipole trap [21], the atoms can be prepared in the lowest internal Zeeman sub-level where they are immune against two-body losses, and full advantage can be taken from the tunability of the scattering length provided by Feshbach resonances [10]. Back in the 1990's we started our Cs experiments with the goal to achieve BEC in an optical dipole trap [22]. In such traps, three-body collisions remain as the dominant source of losses and thus we had to understand the role of three-body decay.…”