title: Indistinguishable entangled photons generated by a light-emitting diode.
abstract: A linear optical quantum computer relies on interference between photonic qubits for logic, and entanglement for near-deterministic operation. Here we measure the interference and entanglement properties of photons emitted by a quantum dot embedded within a light-emitting diode. We show that pairs of simultaneously generated photons are entangled, and indistinguishable from subsequently generated photons. We measure entanglement fidelity of 0.87 and two-photon-interference visibility of 0.60 ± 0.05. The visibility, limited by detector jitter, could be improved by optical cavity designs.
authors.affiliation: Toshiba Research Europe Limited, 208 Science Park, Cambridge CB4 0GZ, United Kingdom.
authors.forename: R M
authors.initials: RM
authors.lastname: Stevenson
authors.forename: C L
authors.initials: CL
authors.lastname: Salter
authors.forename: J
authors.initials: J
authors.lastname: Nilsson
authors.forename: A J
authors.initials: AJ
authors.lastname: Bennett
authors.forename: M B
authors.initials: MB
authors.lastname: Ward
authors.forename: I
authors.initials: I
authors.lastname: Farrer
authors.forename: D A
authors.initials: DA
authors.lastname: Ritchie
authors.forename: A J
authors.initials: AJ
authors.lastname: Shields