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arXiv · cond-mat/0310719

Entanglement interferometry for precision measurement of atomic scattering properties

Abstract

We report on a two-particle matter wave interferometer realized with pairs of trapped 87Rb atoms. Each pair of atoms is confined at a single site of an optical lattice potential. The interferometer is realized by first creating a coherent spin-mixture of the two atoms and then tuning the inter-state scattering length via a Feshbach resonance. The selective change of the inter-state scattering length leads to an entanglement dynamics of the two-particle state that can be detected in a Ramsey interference experiment. This entanglement dynamics is employed for a precision measurement of atomic interaction parameters. Furthermore, the interferometer allows to separate lattice sites with one or two atoms in a non-destructive way.

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Artur Widera, Olaf Mandel, Markus Greiner, Susanne Kreim, Theodor W. Hänsch, Immanuel Bloch. 2003-10-30. Entanglement interferometry for precision measurement of atomic scattering properties. https://doi.org/10.1103/physrevlett.92.160406

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