dorsal/arxiv
View SchemaDistributing entanglement and single photons through an intra-city, free-space quantum channel
| Authors | K. J. Resch, M. Lindenthal, B. Blauensteiner, H. R. Boehm, A. Fedrizzi, C. Kurtsiefer, A. Poppe, T. Schmitt-Manderbach, M. Taraba, R. Ursin, P. Walther, H. Weier, H. Weinfurter, A. Zeilinger |
|---|---|
| Categories | |
| ArXiv ID | quant-ph/0501008 |
| URL | https://arxiv.org/abs/quant-ph/0501008 |
| DOI | 10.1364/OPEX.13.000202 |
| Journal | Opt. Express 13, 202-209 (2005) |
Abstract
We have distributed entangled photons directly through the atmosphere to a receiver station 7.8 km away over the city of Vienna, Austria at night. Detection of one photon from our entangled pairs constitutes a triggered single photon source from the sender. With no direct time-stable connection, the two stations found coincidence counts in the detection events by calculating the cross-correlation of locally-recorded time stamps shared over a public internet channel. For this experiment, our quantum channel was maintained for a total of 40 minutes during which time a coincidence lock found approximately 60000 coincident detection events. The polarization correlations in those events yielded a Bell parameter, S=2.27/pm0.019, which violates the CHSH-Bell inequality by 14 standard deviations. This result is promising for entanglement-based free-space quantum communication in high-density urban areas. It is also encouraging for optical quantum communication between ground stations and satellites since the length of our free-space link exceeds the atmospheric equivalent.
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"abstract": "We have distributed entangled photons directly through the atmosphere to a\nreceiver station 7.8 km away over the city of Vienna, Austria at night.\nDetection of one photon from our entangled pairs constitutes a triggered single\nphoton source from the sender. With no direct time-stable connection, the two\nstations found coincidence counts in the detection events by calculating the\ncross-correlation of locally-recorded time stamps shared over a public internet\nchannel. For this experiment, our quantum channel was maintained for a total of\n40 minutes during which time a coincidence lock found approximately 60000\ncoincident detection events. The polarization correlations in those events\nyielded a Bell parameter, S=2.27/pm0.019, which violates the CHSH-Bell\ninequality by 14 standard deviations. This result is promising for\nentanglement-based free-space quantum communication in high-density urban\nareas. It is also encouraging for optical quantum communication between ground\nstations and satellites since the length of our free-space link exceeds the\natmospheric equivalent.",
"arxiv_id": "quant-ph/0501008",
"authors": [
"K. J. Resch",
"M. Lindenthal",
"B. Blauensteiner",
"H. R. Boehm",
"A. Fedrizzi",
"C. Kurtsiefer",
"A. Poppe",
"T. Schmitt-Manderbach",
"M. Taraba",
"R. Ursin",
"P. Walther",
"H. Weier",
"H. Weinfurter",
"A. Zeilinger"
],
"categories": [
"quant-ph"
],
"doi": "10.1364/OPEX.13.000202",
"journal_ref": "Opt. Express 13, 202-209 (2005)",
"title": "Distributing entanglement and single photons through an intra-city, free-space quantum channel",
"url": "https://arxiv.org/abs/quant-ph/0501008"
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