Possibility of all optically-cooled and trapped Cs-133 atomic BEC

The experimental progress on rf evaporative cooling of Cs-133 atomic sample in recent year is reviewed, and the difficulty of magnetically trapped Cs- 133 atomic Bose-Einstein condensation (BEC) is analyzed. In this paper, we propose an all-optically-cooled and -trapped Cs-133 BEC scheme, which is co mposed of a pyramidal-hollow-beam gravito-optical trap (PHB GOT) from a dio de laser (lambda = 0.852 mum) and a conical-hollow-beam (CHB) GOT from an A r+ laser (<(<lambda>)over bar> = 0.5013 mum) In the PHB GOT, the cold atoms experience an efficient hollow-beam induced Sisyphus cooling (i.e., intens ity gradient cooling) and repumpimg-beam induced geometric cooling, and the y will be cooled to a few photon-recoil limits ( similar to2 muK) from MOT' s temperature ( similar to 60 muK) Whereas in the Ar+ hollow-laser-beam tra p, cold atoms will be further cooled by Raman cooling (or velocity-selectio n coherent population trapping) and compressed by a blue-detuned covering b eam. We have performed Monte-Carlo simulations for PHB cooling process, cal culated the optical potential for Cs-133 atoms in Ar+ hollow laser beam, an d estimated total collision loss and atomic density. Our study shows that t he realization of an optically-cooled and -trapped BEC of Cs-133 atoms may be possible in our all-optical dipole trap.