We propose an all-optically-cooled and-trapped Cs BEC scheme, which is composed of a pyramidal-hollow-beam gravito-optical trap (PHB GOT) from a diode laser and a conical-hollow-beam (CHB) GOT from an Ar~+ laser. In the PHB GOT, the cold atoms experience an effiicent hollow-beam induced Sisyphus cooling and repumping-beam induced geometric cooling, and they will be cooled to a few photon-recoil limits from MOT's temperature (approx60 um K), Whereas in the Ar~+ hollow-laser-beam trap,cold atoms will be further cooled by Raman cooling and compressed by a blue-detuned cover beam. We have performed Monte-Carlo simulations for PHB cooling process, calculated the optical potential for ~133Cs atoms in Ar~+ hollow laser beam, and estimated total atomic loss and density. Our study shows that an optically-trapped Bose-Einstein condensation (BEC) of ~133Cs atoms may be observed in our all-optical dipole trap.
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