Abstract

A small number of atoms that are confined to dimensions on the order of an optical wavelength are expected to exhibit novel collective behavior, including superradiance, subradiance, and unusual photon statistics and spatial correlations. We have identified a technique by which such a wavelength-sized atomic point sample may be realized in the laboratory. Atoms that are strongly confined in an optical dipole-force potential may be laser-cooled via stimulated and spontaneous Raman transitions between ground state atomic sublevels. Because the ac Stark shift of the two lower state sublevels is the same, the atoms may be cooled and trapped simultaneously. Also, interatomic radiation pressure and collisional effects can be kept to a minimum in a dipole force trap. We are currently pursuing such experiments using laser-cooled Rb atoms. We have successfully loaded laser-cooled Rb into a dipole force trap and have also driven the stimulated Raman transitions between the Rb ground state sublevels. We will report on our experimental progress and discuss their application to fundamental investigations in quantum optics.

© 1992 Optical Society of America