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Roughness suppression via rapid current modulation on an atom chip

Jean-Baptiste Trebbia·Carlos Leonardo Garrido Alzar·Ronald Cornelussen·Christoph I. Westbrook·Isabelle Bouchoule
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Abstract

We present a method to suppress the potential roughness of a wire-based, magnetic atom guide: modulating the wire current at a few tens of kHz, the potential roughness, which is proportional to the wire current, averages to zero. Using ultra-cold $^{87}{\rm Rb}$ clouds, we show experimentally that modulation reduces the roughness by at least of a factor five without measurable heating or atom loss. This roughness suppression results in a dramatic reduction of the damping of center of mass oscillations.

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Jean-Baptiste Trebbia, Carlos Leonardo Garrido Alzar, Ronald Cornelussen, Christoph I. Westbrook, Isabelle Bouchoule. 2007-06-20. Roughness suppression via rapid current modulation on an atom chip. https://arxiv.org/abs/quant-ph/0701207

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