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Decoherence of cold atomic gases in magnetic micro-traps

C. Schroll·W. Belzig·C. Bruder
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Abstract

We derive a model to describe decoherence of atomic clouds in atom-chip traps taking the excited states of the trapping potential into account. We use this model to investigate decoherence for a single trapping well and for a pair of trapping wells that form the two arms of an atom interferometer. Including the discrete spectrum of the trapping potential gives rise to a decoherence mechanism with a decoherence rate $Γ$ that scales like $Γ\sim 1/r_0^4$ with the distance $r_0$ from the trap minimum to the wire.

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C. Schroll, W. Belzig, C. Bruder. 2003-05-13. Decoherence of cold atomic gases in magnetic micro-traps. https://doi.org/10.1103/physreva.68.043618

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