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Evanescent-wave trapping and evaporative cooling of an atomic gas near two-dimensionality

M. Hammes·D. Rychtarik·B. Engeser·H. -C. Nägerl·R. Grimm
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Abstract

A dense gas of cesium atoms at the crossover to two-dimensionality is prepared in a highly anisotropic surface trap that is realized with two evanescent light waves. Temperatures as low as 100nK are reached with 20.000 atoms at a phase-space density close to 0.1. The lowest quantum state in the tightly confined direction is populated by more than 60%. The system offers intriguing prospects for future experiments on degenerate quantum gases in two dimensions.

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M. Hammes, D. Rychtarik, B. Engeser, H. -C. Nägerl, R. Grimm. 2002-08-16. Evanescent-wave trapping and evaporative cooling of an atomic gas near two-dimensionality. https://doi.org/10.1103/physrevlett.90.173001

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