Postselection-Loophole-Free Bell Test Over an Installed Optical Fiber Network
2015 (English)In: Physical Review Letters, ISSN 0031-9007, E-ISSN 1079-7114, Vol. 115, no 3, 030503- p.Article in journal (Refereed) Published
Device-independent quantum communication will require a loophole-free violation of Bell inequalities. In typical scenarios where line of sight between the communicating parties is not available, it is convenient to use energy-time entangled photons due to intrinsic robustness while propagating over optical fibers. Here we show an energy-time Clauser-Horne-Shimony-Holt Bell inequality violation with two parties separated by 3.7 km over the deployed optical fiber network belonging to the University of Concepcion in Chile. Remarkably, this is the first Bell violation with spatially separated parties that is free of the postselection loophole, which affected all previous in-field long-distance energy-time experiments. Our work takes a further step towards a fiber-based loophole-free Bell test, which is highly desired for secure quantum communication due to the widespread existing telecommunication infrastructure.
Place, publisher, year, edition, pages
American Physical Society , 2015. Vol. 115, no 3, 030503- p.
Electrical Engineering, Electronic Engineering, Information Engineering
IdentifiersURN: urn:nbn:se:liu:diva-120450DOI: 10.1103/PhysRevLett.115.030503ISI: 000357864800002OAI: oai:DiVA.org:liu-120450DiVA: diva2:845599
Funding Agencies|CONICYT [PFB08-024]; Milenio [RC130001]; FONDECYT [11110115, 1150101, 1120067, 1151278]; MINECO, Spain [FIS2011-29400]; FEDER funds; FQXi large grant; CENIIT at Linkoping University; CONICYT; program Science without Borders (CAPES); program Science without Borders (CNPq, Brazil); QWAD-Quantum Waveguides Application and Development [FP7-ICT-2011-9- 600838]2015-08-122015-08-112016-08-31