Mainz 2017 – scientific programme

Parts | Days | Selection | Search | Updates | Downloads | Help

Q: Fachverband Quantenoptik und Photonik

Q 17: Quantum Repeater and Quantum Communication

Q 17.5: Talk

Tuesday, March 7, 2017, 12:00–12:15, P 3

Two-Color Time Entanglement for Quantum Communication — •Tobias Kohl, Chris Müller, and Oliver Benson — AG Nanooptik, Institut für Physik, Humboldt-Universität zu Berlin

Losses over long distances are a big challenge in creating a global quantum communication network. One possibility to minimize those effects is a quantum repeater which can be realized with entangled photons [1]. At certain nodes of a QR these photons have to be matched to dissimilar quantum systems, e.g. a storage or processing unit.

We produce highly non-degenerate photon pairs with wavelengths at the Cs D1 line (894.3 nm) and the telecom O-band (1313.1 nm) by parametric down conversion in a periodically poled Lithium-Niobat crystal. We already demonstrated polarization entanglement [2] when operating in a folded-sandwich geometry. However, polarization is difficult to maintain over long-distance optical fibers. Therefore, we set up a Franson interferometer [3] to create entanglement in time and position.

The goal is to establish a hybrid quantum interface in which we teleport the electronic state of a quantum dot onto a photon at telecom wavelength for long distance communication.

[1] Bussières F., et al. Nature Photonics 8, 775-778 (2014)

[2] Dietz O., et al. Appl. Phys. B 122, 33 (2016)

[3] Franson J. D. Phys. Rev. Lett. 62, 2205 (1989)