All-optical production of Li-6 quantum gases
Authors: Burchianti A., Seman J. A., Valtolina G., Morales A., Inguscio M., Zaccanti M., Roati G.
Autors Affiliation: INO-CNR,via Nello Carrara 1, 50019 Sesto Fiorentino, Italy
LENS and Università di Firenze, Via Nello Carrara 1, 50019 Sesto Fiorentino, Italy
Scuola Normale Superiore, Piazza dei Cavalieri, 7, 56126 Pisa, Italy
Department of Physics, ETH Zurich, 8093 Zurich, Switzerland
INRIM, Strada delle Cacce 91, 10135 Torino, Italy
Abstract: We report efficient production of quantum gases of Li-6 using a sub-Doppler cooling scheme based on the D-1 transition. After loading in a standard magneto-optical trap, an atomic sample of 10(9) atoms is cooled at a temperature of 40 mu K by a bichromatic D-1 gray-molasses. More than 2×10(7) atoms are then transferred into a high-intensity optical dipole trap, where a two-spin state mixture is evaporatively cooled down to quantum degeneracy. We observe that D-1 cooling remains effective in the deep trapping potential, allowing an effective increase of the atomic phase-space density before starting the evaporation. In a total experimental cycle of 11 s, we produce weakly-interacting degenerate Fermi gases of 7×10(5) atoms at T/T-F < 0.1 and molecular Bose-Einstein condensates of up 5x10(5) molecules. We further describe a simple and compact optical system both for high-resolution imaging and for imprinting a thin optical barrier on the atomic cloud; this represents a first step towards the study of quantum tunneling in strongly interacting superfluid Fermi gases.