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Surface Effects in Magnetic Microtraps

J. Fortagh·H. Ott·S. Kraft·C. Zimmermann
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Abstract

We have investigated Bose-Einstein condensates and ultra cold atoms in the vicinity of a surface of a magnetic microtrap. The atoms are prepared along copper conductors at distances to the surface between 300 um and 20 um. In this range, the lifetime decreases from 20 s to 0.7 s showing a linear dependence on the distance to the surface. The atoms manifest a weak thermal coupling to the surface, with measured heating rates remaining below 500 nK/s. In addition, we observe a periodic fragmentation of the condensate and thermal clouds when the surface is approached.

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J. Fortagh, H. Ott, S. Kraft, C. Zimmermann. 2002-10-23. Surface Effects in Magnetic Microtraps. https://doi.org/10.1103/physreva.66.041604

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