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arXiv · 2003.00939

Quantum test of the Universality of Free Fall using rubidium and potassium

H. Albers·A. Herbst·L. L. Richardson·H. Heine·D. Nath·J. Hartwig·C. Schubert·C. Vogt·M. Woltmann·C. Lämmerzahl·S. Herrmann·W. Ertmer·E. M. Rasel·D. Schlippert
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Abstract

We report on an improved test of the Universality of Free Fall using a rubidium-potassium dual-species matter wave interferometer. We describe our apparatus and detail challenges and solutions relevant when operating a potassium interferometer, as well as systematic effects affecting our measurement. Our determination of the E\"otv\"os ratio yields $\eta_{\,\text{Rb,K}}=-1.9\times10^{-7}$ with a combined standard uncertainty of $\sigma_\eta=3.2\times10^{-7}$.

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H. Albers, A. Herbst, L. L. Richardson, H. Heine, D. Nath, J. Hartwig, C. Schubert, C. Vogt, M. Woltmann, C. Lämmerzahl, S. Herrmann, W. Ertmer, E. M. Rasel, D. Schlippert. 2020-03-02. Quantum test of the Universality of Free Fall using rubidium and potassium. https://doi.org/10.1140/epjd/e2020-10132-6

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