A strong UNIQORN presence at ICTON 2019

21st International Conference on Transparent Optical Networks
ICTON 2019
Place: Angers, France
Date: July 9 -13, 2019

The UNIQORN partners will present recent project results at ICTON 2019 during the following dedicated talks!

Flexible entanglement distribution based on WDM and active switching technology

Session: QC I Wednesday, July 10, 9:10-10:50

Hannes Hübel, Bernhard Schrenk, Sophie Zeiger, Fabian Laudenbach and Michael Hentschel  (AIT Austrian institute of Technology)

In future, the distribution of single or entangled photons inside optical networks will be a prerequisite for a general roll-out and adoption of quantum communication technologies. In particular, on-demand routing and active wavelength allocation will be needed to meet the demand of complex network architectures. In the last years several attempts have been made, based either on passive optical WDM technology or active switching of channels. Here we present a novel approach whereby we combine spectral slicing of the emission spectrum of SPDC sources together with space-switches to generate a reconfigurable distribution node for entanglement.  The increased switching complexity offered by our hybrid solution allows us to realise quantum ROADMs with up to three degrees.

Modelling Weak-Coherent CV-QKD Systems Using a Classical Simulation Framework

Session: QC III Wednesday, July 10, 14:20-16:20

Sören Kreinberg(1), Igor Koltchanov(1), Piotr Novik(2), Saleem Alreesh(1), Fabian Laudenbach(3), Christoph Pacher(3), Hannes Hübel(3), André Richter(1)

(1) VPIphotonics GmbH, Carnotstr. 6, 10587 Berlin, Germany
(2) VPI Development Center, ul. Filimonova 15-50831, 220037 Minsk, Belarus
(3) Austrian Institute of Technology GmbH, Donau-City-Str. 1, 1220 Vienna, Austria

Due to their compatibility to existing telecom technology, continuous variable (CV) weak coherent state protocols are promising candidates for a broad deployment of quantum key distribution (QKD) technology. We demonstrate how an existing simulation framework for modelling classical optical systems can be utilized for simulations of weak-coherent CV-QKD links. The quantum uncertainties for the measured characteristics of coherent signals are modelled in the electrical domain by shot noise, while a coherent signal in the optical domain is described by its quadrature components. We simulate various degradation effects such as attenuation, laser RIN, Raman noise (from classical channels in the same fibre), and device imperfections and compare the outcome with analytical theory. Having complemented the physical simulation layer by the post-processing layer (reconciliation and privacy amplification), we are able to estimate secure key rates from simulations, greatly boosting the development speed of practical CV-QKD schemes and implementations.

Coexistence of discrete-variable QKD with WDM classical signals in the C-band for fiber access environments

Session: QC V Thursday, July 11, 8:30-10:10

D. Zavitsanos (1), G. Giannoulis (1), A. Raptakis (1), C. Papananos (1), F. Setaki (2), E. Theodoropoulou (2), G. Lyberopoulos (2), Ch. Kouloumentas (1), (3), and H. Avramopoulos (1)

(1) National Technical University of Athens, Greece
(2) COSMOTE Kinites Tilepikoinonies A.E., Athens, Greece
(3) Optagon Photonics, Athens, Greece

In this paper, a coexistence scheme between a Discrete-Variable Quantum Key Distribution (DV-QKD) and four bidirectional classical channels in a Passive Optical Network (PON) topology is theoretically investigated. The study aims to explore the imposed limitations considering the coexistence of weak quantum channels with realistic traffic flows of classical streams through shared fiber infrastructures. Based on a ‘plug and play’ phase coding DV-QKD implementation, we conducted numerical simulations of the QBER and the secure key rate for fiber distances up to 10km. The reported results suggest that in a fixed C-band grid, the spectral isolation between classical and quantum channels is essential at dense grids. By removing the leakage noise through stronger spectral isolation, the photons linked with the Raman scattering becomes the dominant noise source, since this mechanism covers an ultra-broadband window and gets stronger as the propagation distance increases.

Official ICTON 2019 website:http://www.icton2019.com/