Details

Autor(en) / Beteiligte

• Erven, C.
• Meyer-Scott, E.
• Fisher, K.
• Lavoie, J.
• Higgins, B. L.
• Yan, Z.
• Pugh, C. J.
• Bourgoin, J.-P.
• Prevedel, R.
• Shalm, L. K.
• Richards, L.
• Gigov, N.
• Laflamme, R.
• Weihs, G.
• Jennewein, T.
• Resch, K. J.

Titel

Experimental three-photon quantum nonlocality under strict locality conditions

Ist Teil von

• Nature photonics, 2014-04, Vol.8 (4), p.292-296

Ort / Verlag

London: Nature Publishing Group UK

Erscheinungsjahr

2014

Quelle

Alma/SFX Local Collection

Beschreibungen/Notizen

• Quantum correlations, often observed as violations of Bell inequalities 1 , 2 , 3 , 4 , 5 , are critical to our understanding of the quantum world, with far-reaching technological 6 , 7 , 8 , 9 and fundamental impact. Many tests of Bell inequalities have studied pairs of correlated particles. However, interest in multi-particle quantum correlations is driving the experimental frontier to test larger systems. All violations to date require supplementary assumptions that open results to loopholes, the closing of which is one of the most important challenges in quantum science. Seminal experiments have closed some loopholes 10 , 11 , 12 , 13 , 14 , 15 , 16 , but no experiment has closed locality loopholes with three or more particles. Here, we close both the locality and freedom-of-choice loopholes by distributing three-photon Greenberger–Horne–Zeilinger entangled states 17 to independent observers. We measured a violation of Mermin's inequality 18 with parameter 2.77 ± 0.08, violating its classical bound by nine standard deviations. These results are a milestone in multi-party quantum communication 19 and a significant advancement of the foundations of quantum mechanics 20 . Violation of the classical bound of the three-particle Mermin inequality by nine standard deviations is experimentally demonstrated by closing both the locality and freedom-of-choice loopholes; only the fair-sampling assumption is required. To achieve this, a light source for producing entangled multiphoton states and measurement technologies for precise timing and efficient detection were developed.