title: Active temporal multiplexing of indistinguishable heralded single photons.
abstract: It is a fundamental challenge in quantum optics to deterministically generate indistinguishable single photons through non-deterministic nonlinear optical processes, due to the intrinsic coupling of single- and multi-photon-generation probabilities in these processes. Actively multiplexing photons generated in many temporal modes can decouple these probabilities, but key issues are to minimize resource requirements to allow scalability, and to ensure indistinguishability of the generated photons. Here we demonstrate the multiplexing of photons from four temporal modes solely using fibre-integrated optics and off-the-shelf electronic components. We show a 100% enhancement to the single-photon output probability without introducing additional multi-photon noise. Photon indistinguishability is confirmed by a fourfold Hong-Ou-Mandel quantum interference with a 91 ± 16% visibility after subtracting multi-photon noise due to high pump power. Our demonstration paves the way for scalable multiplexing of many non-deterministic photon sources to a single near-deterministic source, which will be of benefit to future quantum photonic technologies.
authors.affiliation: Centre for Ultrahigh bandwidth Devices for Optical Systems (CUDOS), Institute of Photonics and Optical Science (IPOS), School of Physics, University of Sydney, New South Wales 2006, Australia.
authors.forename: C
authors.initials: C
authors.lastname: Xiong
authors.affiliation: Centre for Ultrahigh bandwidth Devices for Optical Systems (CUDOS), Institute of Photonics and Optical Science (IPOS), School of Physics, University of Sydney, New South Wales 2006, Australia.
authors.forename: X
authors.initials: X
authors.lastname: Zhang
authors.affiliation: School of Electrical and Information Engineering, University of Sydney, New South Wales 2006, Australia.|Department of Communication Engineering, School of Information Engineering, Guangdong University of Technology, 510006 Guangdong, China.
authors.forename: Z
authors.initials: Z
authors.lastname: Liu
authors.affiliation: Centre for Ultrahigh bandwidth Devices for Optical Systems (CUDOS), Institute of Photonics and Optical Science (IPOS), School of Physics, University of Sydney, New South Wales 2006, Australia.
authors.forename: M J
authors.initials: MJ
authors.lastname: Collins
authors.affiliation: Centre for Ultrahigh bandwidth Devices for Optical Systems (CUDOS), Institute of Photonics and Optical Science (IPOS), School of Physics, University of Sydney, New South Wales 2006, Australia.|School of Electrical and Information Engineering, University of Sydney, New South Wales 2006, Australia.
authors.forename: A
authors.initials: A
authors.lastname: Mahendra
authors.affiliation: CUDOS and MQ Photonics Research Centre, Department of Physics and Astronomy, Macquarie University, New South Wales 2109, Australia.
authors.forename: L G
authors.initials: LG
authors.lastname: Helt
authors.affiliation: CUDOS and MQ Photonics Research Centre, Department of Physics and Astronomy, Macquarie University, New South Wales 2109, Australia.
authors.forename: M J
authors.initials: MJ
authors.lastname: Steel
authors.affiliation: CUDOS, Laser Physics Centre, Australian National University, Canberra, Australian Capital Territory 2601, Australia.
authors.forename: D-Y
authors.initials: DY
authors.lastname: Choi
authors.affiliation: Department of Electrical and Electronic Engineering, University of Melbourne, Parkville, Victoria 3010, Australia.
authors.forename: C J
authors.initials: CJ
authors.lastname: Chae
authors.affiliation: School of Electrical and Information Engineering, University of Sydney, New South Wales 2006, Australia.
authors.forename: P H W
authors.initials: PH
authors.lastname: Leong
authors.affiliation: Centre for Ultrahigh bandwidth Devices for Optical Systems (CUDOS), Institute of Photonics and Optical Science (IPOS), School of Physics, University of Sydney, New South Wales 2006, Australia.
authors.forename: B J
authors.initials: BJ
authors.lastname: Eggleton