arXiv subjects

J. A. W. van Houwelingen

Publications and source records attributed to J. A. W. van Houwelingen.

6 recordsLinked to original sources

arXiv2010

Simple synchronization of independent picosecond photon sources for quantum communication experiments

An essential requirement for the future of quantum communication is the capability to create undistinguishable photons at distant locations. The main challenge is to control the various sources of timing jitter in order to conserve temporal undistinguishability. We report on a system that enables a large tolerance against such jitter by using synchronized sources of photons with coherence lengths on the order of centimeters.

quant-ph↗

arXiv2008

Space-like Separation in a Bell Test assuming Gravitationally Induced Collapses

We report on a Bell experiment with space-like separation assuming that the measurement time is related to gravity-induced state reduction. Two energy-time entangled photons are sent through optical fibers and directed into unbalanced interferometers at two receiving stations separated by 18 km. At each station, the detection of a photon triggers the displacement of a macroscopic mass. The timing ensures space-like separation from the moment a photon enters its interferometer until the mass has moved. 2-photon interference fringes with a visibility of up to 90.5% are obtained, leading to a violation of Bell inequality.

quant-ph↗

arXiv2006

Quantum teleportation over the Swisscom telecommunication network

We present a quantum teleportation experiment in the quantum relay configuration using the installed telecommunication network of Swisscom. In this experiment, the Bell state measurement occurs well after the entanglement has been distributed, at a point where the photon upon which data is teleported is already far away, and the entangled qubits are photons created from a different crystal and laser pulse than the teleported qubit. A raw fidelity of 0.93+/-0.04 has been achieved using a heralded single-photon source.

quant-ph↗

arXiv2006

Experimental Quantum Teleportation with a 3-Bell-state Analyzer

We present a Bell-state analyzer for time-bin qubits allowing the detection of three out of four Bell-states with linear optics, two detectors and no auxiliary photons. The theoretical success rate of this scheme is 50%. A teleportation experiment was performed to demonstrate its functionality. We also present a teleportation experiment with a Fidelity larger than the cloning limit of F=5/6.

quant-ph↗

arXiv2005

Quantum Teleportation with a 3-Bell-state Analyzer

We present a novel Bell-state analyzer for time-bin qubits allowing the detection of three out of four Bell-states with linear optics, only two detectors and no auxiliary photons. The theoretical success rate of this scheme is 50%. A teleportation experiment was performed to demonstrate its functionality. We also present a teleportation experiment with a fidelity larger than the cloning limit.

quant-ph↗

arXiv2004

Long distance entanglement swapping with photons from separated sources

We report the first experimental realization of entanglement swapping over large distances in optical fibers. Two photons separated by more than two km of optical fibers are entangled, although they never directly interacted. We use two pairs of time-bin entangled qubits created in spatially separated sources and carried by photons at telecommunication wavelengths. A partial Bell state measurement is performed with one photon from each pair which projects the two remaining photons, formerly independent onto an entangled state. A visibility high enough to violate a Bell inequality is reported, after both photons have each travelled through 1.1 km of optical fiber.

quant-ph↗