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arXiv · 2206.08560

A matter wave Rarity-Tapster interferometer to demonstrate non-locality

Kieran F. Thomas·Bryce M. Henson·Yu Wang·Robert J. Lewis-Swan·Karen V. Kheruntsyan·Sean S. Hodgman·Andrew G. Truscott
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Abstract

We present an experimentally viable approach to demonstrating quantum non-locality in a matter wave system via a Rarity-Tapster interferometer using two $s$-wave scattering halos generated by colliding helium Bose-Einstein condensates. The theoretical basis for this method is discussed, and its suitability is experimentally quantified. As a proof of concept, we demonstrate an interferometric visibility of $V=0.42(9)$, corresponding to a maximum CSHS-Bell parameter of $S=1.1(1)$, for the Clauser-Horne-Shimony-Holt (CHSH) version of the Bell inequality, between atoms separated by $\sim 4$ correlation lengths. This constitutes a significant step towards a demonstration of a Bell inequality violation for motional degrees of freedom of massive particles and possible measurements of quantum effects in a gravitationally sensitive system.

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BibTeXRIS

Kieran F. Thomas, Bryce M. Henson, Yu Wang, Robert J. Lewis-Swan, Karen V. Kheruntsyan, Sean S. Hodgman, Andrew G. Truscott. 2022-06-17. A matter wave Rarity-Tapster interferometer to demonstrate non-locality. https://doi.org/10.1140/epjd%2Fs10053-022-00551-y

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