Nonlocality tests with momentum-entangled pairs of ultracold metastable helium atoms

by Dr Sean Hodgman (Australian National University)

Tuesday 2 Sept 2025, 15:00 → 16:00 Europe/Vienna

Nonlocal entanglement between pair-correlated particles is a highly counter-intuitive aspect of quantum mechanics. While the rigorous Bell’s inequality framework has enabled the demonstration of such entanglement in photons and atomic internal states, no experiment has yet involved motional states of massive particles. Here we report the experimental observation of nonlocal correlations in motional states of momentum-entangled ultracold helium atoms, with entanglement generated via s-wave collisions. Using a Rarity-Tapster interferometer and a Bell-test framework, we observe atom-atom correlations sufficient to exclude a range of local hidden variable theories. This system could be extended to an entangled state of different mass atoms generated between 3He* and 4He* collisions, and potentially open new avenues for studying gravitational effects in quantum states.

Topic: Nonlocality tests with momentum-entangled pairs of ultracold metastable helium atoms
Time: Sep 2, 2025 03:00 PM Amsterdam, Berlin, Rome, Stockholm, Vienna
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https://oeaw-ac-at.zoom.us/j/69160813463?pwd=xZh7lnpacTFb3619TkdOEaabmalJLt.1

Meeting ID: 691 6081 3463
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