A platform approach towards hybrid photonic integration and assembly for communications, sensing, and quantum technologies based on a polymer waveguide technology

Title

A platform approach towards hybrid photonic integration and assembly for communications, sensing, and quantum technologies based on a polymer waveguide technology

Authors

Moritz Kleinert, Madeleine Nuck, Hauke Conradi, David de Felipe, Martin Kresse, Walter Brinker, Crispin Zawadzki, Norbert Keil, Martin Schell

Abstract

We present functionalities of photonic integrated circuits and a generic assembly approach for their hybrid integration with other components in the polymer waveguide platform PolyBoard. In addition to standard integrated optics capabilities, the PolyBoard approach allows for the realization of flexible interconnects, the fabrication of multilayer waveguide structures with low intra-layer coupling losses, and the integration of bulk optical crystals in on-chip free-space sections. These functionalities enable PICs with applications ranging from communications, via sensing, to quantum technology. The semiautomated assembly process presented in the second part of this paper ensures the compatibility of all individual functionalities and the scalability of the developed approaches towards production.

Venue

2019 IEEE CPMT Symposium Japan (ICSJ)

Place and Date

Kyoto, Japan, 18-20 November 2019

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Differential Phase-Shift QKD in a 2:16-Split Lit PON with 19 Carrier-Grade Channels

Title

Differential Phase-Shift QKD in a 2:16-Split Lit PON with 19 Carrier-Grade Channels

Authors

N. Vokić, D. Milovančev, B. Schrenk, M. Hentschel, H. Hübel

Abstract

We investigate the practical network integration of differential phase shift quantum key distribution following a cost-optimized deployment scheme where complexity is offloaded to a centralized location. User terminal equipment for quantum state preparation at 1 GHz symbol rate is kept technologically lean through use of a directly-modulated laser as optical encoder. Integration in a passive optical network infrastructure is experimentally studied for legacy and modern optical access standards. We analyze the implications that result from Raman scattering arising from different spectral allocations of the classical channels in the O-, S-, C- and L-band, and prove that the quantum channel can co-exist with up to 19 classical channels of a fully-loaded modern access standard. Secure-key generation at a rate of 5.1×10-7 bits/pulse at a quantum bit error ratio of 3.28% is obtained over a 13.5 km reach, 2:16 split passive network configuration. The high power difference of 93.8 dB between launched classical and quantum signals in the lit access network leads to a low penalty of 0.52% in terms of error ratio.

Venue

IEEE J. Sel. Topics in Quantum Electron., vol. 26, no. 3, p. 6400309, May 2020.

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Analysis of the trusted-device scenario in continuous-variable quantum key distribution

Title

Analysis of the trusted-device scenario in continuous-variable quantum key distribution

Authors

Fabian Laudenbach, Christoph Pacher

Abstract 

The assumption that detection and/or state-preparation devices used for continuous-variable quantum key distribution (CV-QKD) are beyond influence of potential eavesdroppers leads to a significant performance enhancement in terms of achievable key rate and transmission distance. We provide a detailed and comprehensible derivation of the Holevo bound in this so-called trusted-device scenario. Modelling an entangling-cloner attack and using some basic algebraic matrix transformations, we show that the computation of the Holevo bound can be reduced to the solution of a quadratic equation. As an advantage of our derivation, the mathematical complexity of our solution does not increase with the number of trusted-noise sources. Finally, we provide a numerical evaluation of our results, illustrating the counter-intuitive fact that an appropriate amount of trusted receiver loss and noise can even be beneficial for the key rate.

Venue

Advanced Quantum Technologies, Vol 2. Issue 11, November 2019

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Adding artificial noise for code rate matching in continuous-variable quantum key distribution

Title

Adding artificial noise for code rate matching in continuous-variable quantum key distribution

Authors

Sören Kreinberg, Igor Koltchanov, André Richter

Abstract

The reconciliation step of continuous-variable quantum key distribution protocols usually involves forward error correction codes. Matching the code rate and the signal-to-noise ratio (SNR) of the quantum channel is required to achieve the high reconciliation efficiencies that are crucial for long distance links. Puncturing and shortening is a way to adapt the code rate to the SNR at the cost of a slightly reduced reconciliation efficiencies. Instead of adapting the code rate to the SNR, we propose to add a controlled amount of artificial noise to the measured data, so that the resulting SNR could be reduced to match the given code rate. We show that our method can compete with puncturing and shortening and even outperform it in high-loss, high-excess noise scenarios.

Venue

ArXiv.org

Place and Date

https://arxiv.org/abs/1905.04925, Submitted on 13 May 2019

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Flexible User/Cloud-Centric Entanglement Distribution with Synthesizable Network Node

Title

Flexible User/Cloud-Centric Entanglement Distribution with Synthesizable Network Node

Authors

Fabian Laudenbach, Bernhard Schrenk, Martin Achleitner, Nemanja Vokic, Dinka Milovancev, Hannes Hübel

Abstract

The practical roll-out of quantum communication technologies in optical networks and the adoption of novel quantum applications demand the distribution of single or entangled photons. Flexibility and dynamicity is paramount for the provision of quantum resources, in order to scale with the number of users and to meet the demand of complex network architectures. We present a quantum network architecture that features this degree of reconfigurability, without being restricted to a rigid physical-layer network based on purely passive multiplexing componentry. We leverage spectral assets of photon-pair sources, from the short-wavelength band to the L-band, and agile spatial switching at a remote optical network node in order to realize a flexible distribution map that features different flavors, reaching from cloud-centric to user-centric quantum connectivity. Entanglement distribution is experimentally demonstrated at high visibility for five users in a 17-km reach, tree-shaped optical network. The delivered photon rate can be dynamically adjusted between the users by a factor of 2.5. Penalty-free operation is confirmed for integrating a co-existing classical control channel within the quantum.

Venue

Journal of Selected Topics in Quantum Electronics (JSTQE)

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We will be at Quantum.Tech in London!

Our project coordinator Hannes Hübel will be speaking at the 2nd edition of Quantum.Tech, which is being held at Twickenham Stadium, London, 20-22 April 2020.

Quantum.Tech is the world’s first, and largest event bringing together industry, research institutions, government agencies, and investors whose primary goal is to drive forward the commercialisation of Quantum technologies.

UNIQORN is very much looking forward to being a part of this event where 80 other world-class speakers from the entire Quantum ecosystem will participate.

If you’d like to view the full programme or learn more about this event go to: www.quantumtechcongress.co.uk , or to stay up to date on Twitter @QuantumTech_ #QT2020

We hope you will join us at Quantum.Tech this April!

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See you at OFC 2020

Part of our work will be presented by our partner AIT Austrian Institute of Technology at OFC 2020 on 8 – 12 March at San Diego Convention Center, San Diego, California, USA.

  • Monday 9 March 2020 at 11:45 – Room 9

F. Laudenbach, B. Schrenk, M. Achleitner, N. Vokic, D. Milovancev, and H. Hübel, “Flexible Entanglement Distribution Overlay for Cloud/Edge DC Interconnect as Seed for IT-Secure Primitives,” in Proc. OFC’20, San Diego, United States, Mar. 2020, M2K.5

  • Monday 9 March 2020 at 17:30 – Room 1A

N. Vokic, D. Milovancev, W. Boxleitner, H. Hübel, and B. Schrenk, “Compact Differential Phase-Shift Quantum Receiver Assisted by a SOI / BiCMOS Micro-Ring Resonator,” in Proc. OFC’20, San Diego, United States, Mar. 2020, M4A.4

  • Wednesday 11 March 2020 – Poster Session Exhibition Hall B

N. Vokic, D. Milovancev, B. Schrenk, M. Hentschel, and H. Hübel, “Deployment Opportunities for DPS-QKD in the Co-Existence Regime of Lit GPON / NG-PON2 Access Networks,” in Proc. OFC’20, San Diego, United States, Mar. 2020, W2A.56

See you there!

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UNIQORN at INFOCOM World 2019

Our partner COSMOTE presented the UNIQORN project in the INFOCOM World Conference took place in Athens, Greece on the 26th of November 2019.

This year’s InfoCom World, was focused on suggestions, implementations and plans, for the development of the Smart Home industry, as well as challenges, opportunities and prospects.

During the “Prospects and Challenges for Developing Innovative Applications and 5G Services” workshop the UNIQORN representatives had the chance to discuss and exchange ideas with many other interesting projects in the field.

 

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D8.4 Promotion video availability

Contributing Partners

AIT

Executive Summary

In this document we present the official UNIQORN video, which can be used by the project partners and the European Commission to further communicate the scope of the project.
The UNIQORN video explains in simple words the project’s ambition and idea and it can be found on the project’s website as well as on the project’s YouTube channel.
UNIQORN Video: https://youtu.be/SJKmg-qsA_o

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General framework for the analysis of imperfections in nonlinear systems

Title

General framework for the analysis of imperfections in nonlinear systems

Authors

Matteo Santandrea, Michael Stefszky, and Christine Silberhorn

Abstract

In this Letter, we derive a framework to understand the effect of imperfections on the phase-matching spectrum of a wide class of nonlinear systems. We show that this framework is applicable to many physical systems, such as waveguides or fibers. Furthermore, this treatment reveals that the product of the system length and magnitude of the imperfections completely determines the phase-matching properties of these systems, thus offering a general rule for system design. Additionally, our framework provides a simple method to compare the performance of a wide range of nonlinear systems.

Venue 

Optics Letters, 15 November 2019, Volume 44, Issue 22, pp. 5394-5649

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