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arXiv · 2010.15796

Momentum Entanglement for Atom Interferometry

F. Anders·A. Idel·P. Feldmann·D. Bondarenko·S. Loriani·K. Lange·J. Peise·M. Gersemann·B. Meyer·S. Abend·N. Gaaloul·C. Schubert·D. Schlippert·L. Santos·E. Rasel·C. Klempt
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Abstract

Compared to light interferometers, the flux in cold-atom interferometers is low and the associated shot noise large. Sensitivities beyond these limitations require the preparation of entangled atoms in different momentum modes. Here, we demonstrate a source of entangled atoms that is compatible with state-of-the-art interferometers. Entanglement is transferred from the spin degree of freedom of a Bose-Einstein condensate to well-separated momentum modes, witnessed by a squeezing parameter of -3.1(8) dB. Entanglement-enhanced atom interferometers open up unprecedented sensitivities for quantum gradiometers or gravitational wave detectors.

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F. Anders, A. Idel, P. Feldmann, D. Bondarenko, S. Loriani, K. Lange, J. Peise, M. Gersemann, B. Meyer, S. Abend, N. Gaaloul, C. Schubert, D. Schlippert, L. Santos, E. Rasel, C. Klempt. 2020-10-29. Momentum Entanglement for Atom Interferometry. https://doi.org/10.1103/physrevlett.127.140402

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