Journal of Physics Conference Series

Expansion of laser cooled atomic clouds in a near-resonant laser field

Swarupananda Pradhan, B. N. Jagatap

Published Sep 1, 2007• 0 citations

Abstract

Expansion of a cold cloud of cesium atoms trapped in a magneto-optical trap is studied by switching off a pair of counter propagating trapping beams. This corresponds to 1-D expansion of the cold cloud in presence of near resonant laser beams that are orthogonal to the expansion direction. Fluorescence imaging of the expanding cloud shows that the dynamics of expansion is complex and includes three distinctive temporal features- initial contraction followed by ballistic expansion and eventually sputtering of the cloud to leave a core that exhibits damped expansion. These are respectively related to the reduction in the repulsive radiation trapping force, initial temperature of the cold cloud and the stochastic heating arising from the random nature of the photon absorption and emission processes.

DOI: 10.1088/1742-6596/80/1/012042

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