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Characterization of fiber-generated entangled photon pairs with superconducting single-photon detectors
Published
Author(s)
Chuang Liang, Fook L. Kim, Milja Medic, Prem Kumar, Robert Hadfield, Sae Woo Nam
Abstract
We demonstrate the suitability of fiber-generated entangled photon pairs for practical quantum communications in the telecom band by measuring their properties with superconducting single-photon detectors that produce negligible dark counts. The photon pairs are created in approximately 5-ps duration windows at 50 MHz rate while the detectors are operated in ungated free running mode. We obtain a coincidence to accidental-coincidence ratio >80 with raw photon-counting data, i.e., without making any post-measurement corrections. Using a previously demonstrated counter-propagating scheme we also produce polarization-entangled photon pairs at 50-MHz rate, which in coincidence detection directly yield two-photon interference with a fringe visibility >98 %.
Liang, C.
, Kim, F.
, Medic, M.
, Kumar, P.
, Hadfield, R.
and Nam, S.
(2007),
Characterization of fiber-generated entangled photon pairs with superconducting single-photon detectors, Optics Express, [online], https://tsapps.nist.gov/publication/get_pdf.cfm?pub_id=32498
(Accessed October 14, 2025)