All-Optical Production of Quantum Degeneracy and Molecular Bose-Einstein Condensation of 6Li**Supported by the National Natural Science Foundation of China under Grant No 11374101, and the Shanghai Pujiang Program under Grant No 13PJ1402500.

Abstract

We achieve a highly degenerate and strongly interacting Fermi gas in a mixture of the two lowest hyperfine states of 6Li by direct evaporative cooling in a high power crossed optical dipole trap. The trap is loaded from a large atom number magneto-optical trap realized by a laser system of 2.5-W intracavity-frequency-doubled light output at 671 nm. With this system, we also demonstrate the production of a molecular Bose-Einstein condensate (mBEC) of 6Li2, and observe the anisotropic expansion of Fermi gases in the so-called BEC-Bardeen-Cooper-Schrieffer crossover regime.