OBSERVATION OF INTENSITY CORRELATIONS IN THE FLUORESCENCE FROM LASER COOLED ATOMS

We report the observation of intensity correlations in the fluorescenc e from a three dimensional Rb optical molasses. This constitutes a new , non-destructive, in situ probe of laser cooled atoms. The power spec trum of the photocurrent displays a 100 kHz wide feature corresponding to the Doppler width of the atomic velocity distribution, and a narro w peak interpreted as being due to the localization of the atoms in wa velength sized potential wells. As the atoms rms velocity decreases, t he height of the narrow peak increases while its width decreases to as little as 2 kHz. We discuss the potential for new applications of thi s method.