Analysis of Runaway Evaporation and Bose-Einstein Condensation by Time-of-Flight Absorption Imaging

摘要

@@ The achievement of Bose-Einstein condensation (BEC) in our experiment is reported. The process of BEC formation is observed by detecting the image after free expansion, in which the effectiveness of runaway evaporative cooling is shown by measuring the optical density of the atom cloud. About 2 × 105 87Rb atoms in the |F =2, mF = 2> state are condensed into the condensate. The ratio of axial-to-radial size of the condensate released from the magnetic trap is investigated in theory and experiment.