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arXiv · 0908.0623

Engineering of triply entangled states in a single-neutron system

Yuji Hasegawa·Rudolf Loidl·Gerald Badurek·Stephan Sponar·Helmut Rauch
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Abstract

We implemented a triply entangled Greenberger-Horne-Zeilinger(GHZ)-like state and coherently manipulated the spin, path, and energy degrees of freedom in a single neutron system. The GHZ-like state was analyzed with an inequality derived by Mermin: we determined the four expectation values and finally obtained M = 2.558 +/- 0.004 > 2, which exhibits a clear violation of the noncontextual assumption and confirms quantum contextuality.

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Yuji Hasegawa, Rudolf Loidl, Gerald Badurek, Stephan Sponar, Helmut Rauch. 2009-08-05. Engineering of triply entangled states in a single-neutron system. https://doi.org/10.1103/physreva.81.032121

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