title: Time-bin entangled photons from a quantum dot.
abstract: Long-distance quantum communication is one of the prime goals in the field of quantum information science. With information encoded in the quantum state of photons, existing telecommunication fibre networks can be effectively used as a transport medium. To achieve this goal, a source of robust entangled single-photon pairs is required. Here we report the realization of a source of time-bin entangled photon pairs utilizing the biexciton-exciton cascade in a III/V self-assembled quantum dot. We analyse the generated photon pairs by an inherently phase-stable interferometry technique, facilitating uninterrupted long integration times. We confirm the entanglement by performing quantum state tomography of the emitted photons, which yields a fidelity of 0.69(3) and a concurrence of 0.41(6) for our realization of time-energy entanglement from a single quantum emitter.
authors: Institut für Experimentalphysik, Universität Innsbruck, Technikerstr. 25, 6020 Innsbruck, Austria.
authors: Harishankar
authors: H
authors: Jayakumar
authors: Institut für Experimentalphysik, Universität Innsbruck, Technikerstr. 25, 6020 Innsbruck, Austria.
authors: Ana
authors: A
authors: Predojević
authors: Institut für Experimentalphysik, Universität Innsbruck, Technikerstr. 25, 6020 Innsbruck, Austria.
authors: Thomas
authors: T
authors: Kauten
authors: Institut für Experimentalphysik, Universität Innsbruck, Technikerstr. 25, 6020 Innsbruck, Austria.
authors: Tobias
authors: T
authors: Huber
authors: Joint Quantum Institute, National Institute of Standards and Technology & University of Maryland, Gaithersburg, Maryland 20849, USA.
authors: Glenn S
authors: GS
authors: Solomon
authors: 1] Institut für Experimentalphysik, Universität Innsbruck, Technikerstr. 25, 6020 Innsbruck, Austria [2] Institute for Quantum Computing, University of Waterloo, 200 University Ave W, Waterloo, Ontario, Canada N2L 3G1.
authors: Gregor
authors: G
authors: Weihs