Yoann Piétri | LIP6 - Équipe QI

Quantum Key Distribution with Efficient Post-Quantum Cryptography-Secured Trusted Node on a Quantum Network

Wed, 23 Apr 2025 00:00:00 +0000

Quantum Key Distribution (QKD) enables two distant users to exchange a secret key with information-theoretic security, based on the fundamental laws of quantum physics. While it is arguably the most mature application of quantum cryptography, it has inherent limitations in the achievable distance and the scalability to large-scale infrastructures. While the applicability of QKD can be readily increased with the use of intermediary trusted nodes, this adds additional privacy requirements on third parties. In this work, we present an efficient scheme leveraging a trusted node with lower privacy requirements thanks to the use of post-quantum cryptographic techniques, and implement it on a deployed fiber optic quantum communication network in the Paris area.

Yoann Piétri

Wed, 23 Apr 2025 00:00:00 +0000

Personal page here.

Integrated InP-based transmitter for continuous-variable quantum key distribution

Mon, 24 Feb 2025 00:00:00 +0000

Developing quantum key distribution (QKD) systems using monolithic photonic integrated circuits (PICs) can accelerate their adoption by a wide range of markets, thanks to the potential reduction in size, complexity of the overall system, power consumption, and production cost. In this work, we design, fabricate and characterize an InP-based PIC transmitter for continuous-variable (CV) QKD applications. In a proof-of-principle experiment implementing a pulsed Gaussian-modulated coherent state (GMCS) CV-QKD protocol over an optical fiber channel of 11 km, the system showed a performance compatible with a secret key rate of 78 kbps in the asymptotic regime. These results show the potential of InP technologies to integrate CV-QKD systems onto a monolithic platform.

Energetic Analysis of Emerging Quantum Communication Protocols

Mon, 06 Jan 2025 00:00:00 +0000

Communications sécurisées avec des variables quantiques continues

Wed, 01 Jan 2025 00:00:00 +0000

La distribution quantique de clés est une application majeure des technologies quantiques permettant la sécurisation des communications pour des données de haute confidentialité. Son déploiement pratique dans des infrastructures de réseaux nécessite des systèmes de haute performance, compacts et robustes. Dans cet article, sont présentés les concepts de base, les performances et les défis actuels de tels systèmes basés sur le codage de l’information dans des propriétés des quadratures du champ électromagnétique.

Experimental demonstration of Continuous-Variable Quantum Key Distribution with a silicon photonics integrated receiver

Wed, 25 Dec 2024 00:00:00 +0000

Quantum Key Distribution (QKD) is a prominent application in the field of quantum cryptography providing information-theoretic security for secret key exchange. The implementation of QKD systems on photonic integrated circuits (PICs) can reduce the size and cost of such systems and facilitate their deployment in practical infrastructures. To this end, continuous-variable (CV) QKD systems are particularly well-suited as they do not require single-photon detectors, whose integration is presently challenging. Here we present a CV-QKD receiver based on a silicon PIC capable of performing balanced detection. We characterize its performance in a laboratory QKD setup using a frequency multiplexed pilot scheme with specifically designed data processing allowing for high modulation and secret key rates. The obtained excess noise values are compatible with asymptotic secret key rates of 2.4 Mbit/s and 220 kbit/s at an emulated distance of 10 km and 23 km, respectively. These results demonstrate the potential of this technology towards fully integrated devices suitable for high-speed, metropolitan-distance secure communication.

System Integration of High-Performance Continuous-Variable Quantum Key Distribution

Mon, 09 Dec 2024 00:00:00 +0000

Quantum Key Distribution (QKD) is the most prominent and the most mature application of quantum communications. It provides a way for two trusted users, usually named Alice and Bob, once they are provided with a public quantum channel and a public but authenticated classical channel, to exchange a secret key with a security based, not on computational assumptions as it is currently the case with classical cryptography, but on the laws of Physics, and hence, protects even against unbounded adversaries. Combined with a perfectly secure encryption scheme, QKD allows for secure message transmission with information-theoretic security. QKD protocols rely on the no-cloning theorem, and the basic principle that measuring a quantum system inherently modifies its state. These protocols can be mostly divided in two families: Discrete Variable (DV) protocols where the information is encoded on discrete properties of single photons, and Continuous Variable (CV) protocols where the information is encoded on continuous degrees of freedom; and in practice the quadratures of the electromagnetic field. While DV protocols have more maturity, can achieve longer distances, and require less signal processing, their CV counterparts can work at room temperature with high efficiency and at high rate. This thesis mainly focuses on CV-QKD protocols, and tackles several challenges associated with the integration of CV-QKD systems. It showcases the integration of optical components to create a silicon photonics-based receiver for CV-QKD, and benchmark its performance in a full CV-QKD setup, showing an operation up to 23 km of distance. It also showcases the software integration of our CV-QKD experimental platform, as an open-source suite called QOSST: Quantum Open Software for Secure Transmissions. The software performs hardware control, digital signal processing for Alice and Bob (including clock, frequency and phase synchronisation), classical communications with authentication, parameter estimation and secret key rate computation for CV-QKD operations. It is hardware-agnostic and can run in a number of scenarios. It also provides extensive documentation, in the hope that it can help reduce the barrier to enter the world of CV-QKD research, as well as that it can be expanded and improved by other interested groups. The autonomy of the software allows the finding of crucial relationships between signal processing parameters and performance. Using our setup, we demonstrate positive key rates up to 25 km of fiber distance. Our prototype is then integrated into a deployed network in the Paris area, in particular, showing the feasibility on a 15 km deployed link between two remote nodes in Paris. This quantum communication infrastructure is also used to deploy DV-QKD commercial systems, and perform an experiment with a trusted node efficiently secured with Post-Quantum Cryptography on a 57 km link. The energetic cost of CV-QKD is also investigated, both with a hardware-dependent approach and a more theoretical approach to give lower bounds on the energetic consumption. While the theoretical approach gives the global scaling, the hardware dependent approach shows what to expect for the first generation of CV-QKD systems, as well as an interesting comparison between the hardware cost and the post-processing cost. Finally, the detectors used for the CV-QKD setup are considered for another protocol involving the verification of Boson Sampling. Initial simulations and experimental preparation highlight the challenges involved in such an experiment.

Systèmes intégrés de distribution quantique de clés à variables continues à haute performance

Mon, 09 Dec 2024 00:00:00 +0000

Félicitations Dr.Piétri !

Résumé

La Distribution Quantique de Clé (QKD pour Quantum Key Distribution) est l’application la plus proéminente et la plus mature des communications quantiques. Elle permet à deux utilisateurs de confiance, généralement appelés Alice et Bob, lorsqu’ils ont accès à un canal quantique public et à un canal classique public mais authentifié, d’échanger une clé secrète avec une sécurité qui est basée, non pas sur des hypothèses calculatoires comme c’est le cas dans la cryptographie classique, mais sur les lois de la Physique, et ainsi protège même contre un attaquant sans limites.

Les protocoles de QKD se basent sur le théorème de non-clonage, ainsi que sur le principe de base que la mesure d’un système quantique altère son état. Ces protocoles sont majoritairement regroupés en deux familles : les protocoles à Variables Discrètes (DV pour Discrete-Variable), qui encodent l’information sur des propriétés discrètes de photons uniques, et les protocoles à Variables Continues (CV pour Continuous-Variable), qui encodent l’information sur des degrés de liberté continus; en pratique les quadratures du champ électro-magnétique. Bien que les protocoles DV aient plus de maturité, peuvent fonctionner à de plus grandes distances, et bénéficient d’un traitement de signal plus simple, les protocoles CV peuvent fonctionner à température ambiante avec de grandes efficacités et des hauts taux de répétition.

Cette thèse se concentre majoritairement sur des protocoles CV-QKD, et s’adresse à des défis associés à l’intégration de systèmes CV-QKD. Elle montre l’intégration de composants optiques pour créer un récepteur CV-QKD basé sur la photonique sur silicium, et les performances du récepteur sont testées avec une expérience complète de CV-QKD, montrant son opération jusqu’à une distance de 23 km. Elle montre aussi l’intégration logicielle de notre plateforme expérimentale de CV-QKD comme une suite logicielle libre appelée QOSST: Quantum Open Software for Secure Transmissions. Le logiciel effectue le contrôle des équipements, le traitement numérique des signaux pour Alice et Bob (comprenant la synchronisation des horloges, de la fréquence de la phase), les communications classiques avec l’authentification, l’estimation des paramètres et le calcul du taux de clé secrète. Il est agnostique aux équipements et peut être utilisé dans de nombreux scénarios. Une documentation complète est aussi fournie dans l’espoir que le logiciel puisse abaisser les barrières pour initier la recherche en CV-QKD mais aussi pour que d’autres groupes puissent participer à son développement. L’autonomie du logiciel lui permet aussi de trouver des relations cruciales entres les paramètres du traitement numérique des signaux et la performance. En utilisant notre système, nous démontrons des taux de clé positifs jusqu’à 25 km de distance. Notre prototype est ensuite intégré sur un réseau déployé en région Parisienne, en particulier démontrant la faisabilité d’un lien déployé de 15 km entre deux nœuds dans Paris. L’infrastructure de communications quantiques est aussi utilisé pour déployer des systèmes commerciaux DV-QKD, et pour effectuer une expérience avec un nœud de confiance sécurisé avec de la Cryptographie Post-Quantique sur un lien de 57 km.

Le coût énergétique de la CV-QKD est aussi étudié, avec une approche orientée équipements, et une approche plus théorique pour donner une limite basse sur la consommation du protocole. L’approche théorique est, de son côté, capable de donner la tendance globale, alors que l’approche orientée équipements permet de donner un ordre de grandeur sur la consommation des premiers prototypes de CV-QKD, et de trouver une relation intéressante entre le coût énergétique des équipements et le coût des algorithmes de post-traitement.

Finalement, les détecteurs utilisés pour l’expérience de CV-QKD sont mis en considération pour un autre protocole sur la vérification de l’Échantillonnage Bosonique. Les premières simulations ainsi que la préparation expérimentale permettent de mettre en lumière les défis d’une telle expérience.

QOSST : A Highly Modular Open Source Software for Continuous-Variable Quantum Key Distribution

Wed, 13 Nov 2024 00:00:00 +0000

Energetic Analysis of Emerging Quantum Communication Protocols

Wed, 16 Oct 2024 00:00:00 +0000

With the rapid development and early industrialization of quantum technologies, it is of great inter- est to analyze their overall energy consumption before planning for their wide-scale deployments. The evaluation of the total energy requirements of quantum networks is a challenging task: different networks require very disparate techniques to create, distribute, manipulate, detect, and process quantum signals. This paper aims to lay the foundations of a framework to model the energy requirements of different quantum technologies and protocols applied to near-term quantum networks. Different figures of merit are discussed and a benchmark on the energy consumption of bipartite and multipartite network proto- cols is presented. An open-source software to estimate the energy consumption of photonic setups is also provided.

QOSST: An Open Source Software for Continuous-Variable Quantum Key Distribution

Wed, 02 Oct 2024 00:00:00 +0000

Yoann Piétri - Not specified

Wed, 25 Sep 2024 00:00:00 +0000

Not specified

Ce séminaire, donné par Yoann Piétri, aura lieu le 25 September 2024, à 14:0. Il aura lieu en salle Not specified.

Vous trouverez un plan du campus ici.

Résumé

Not specified

Post-Quantum Cryptographically-Secured Trusted Node for Quantum Key Distribution in a Deployed Network

Mon, 02 Sep 2024 00:00:00 +0000

Objective: Reduce the security risks associated with the usage of trusted nodes in a QKD network. Conclusion: The transported QKD key is secure agains honest-curious nodes at a lower key-rate cost than state-of-the-art.

QOSST: A Highly Modular Open Source Platform for Continuous Variable Quantum Key Distribution Applications

Sun, 23 Jun 2024 00:00:00 +0000

We present a highly modular Open Source Software to perform CV-QKD experiments. The software is hardware agnostic and was benchmarked on bulk and integrated receivers, reaching state of the art secret key rates.

Towards an Experimental Implementation of Efficient Verification of Boson Sampling

Sun, 23 Jun 2024 00:00:00 +0000

QOSST: A Highly-Modular Open Source Platform for Experimental Continuous-Variable Quantum Key Distribution

Mon, 29 Apr 2024 00:00:00 +0000

Quantum Key Distribution (QKD) enables secret key exchange between two remote parties with information-theoretic security rooted in the laws of quantum physics. Encoding key information in continuous variables (CV), such as the values of quadrature components of coherent states of light, brings implementations much closer to standard optical communication systems, but this comes at the price of significant complexity in the digital signal processing techniques required for operation at low signal-to-noise ratios. In this work, we wish to lower the barriers to entry for CV-QKD experiments associated to this difficulty by providing a highly modular, open source software that is in principle hardware agnostic and can be used in multiple configurations. We benchmarked this software, called QOSST, using an experimental setup with a locally generated local oscillator, frequency multiplexed pilots and RF-heterodyne detection, and obtained state-of-the-art secret key rates of the order of Mbit/s over metropolitan distances at the asymptotic limit. We hope that QOSST can be used to stimulate further experimental advances in CV-QKD and be improved and extended by the community to achieve high performance in a wide variety of configurations.

Experimental Demonstration of Continuous-Variable Quantum Key Distribution with a Photonic Integrated Receiver and Modular Software

Wed, 22 Nov 2023 00:00:00 +0000

High-speed continuous-variable quantum key distribution with advanced digital signal processing

Sun, 02 Jul 2023 00:00:00 +0000

Continuous-variable quantum key distribution (CV-QKD) is a promising solution for providing high secure key rates in moderate loss channels. A great advantage with respect to discrete-variable (DV) systems is the use of a technology similar to the one used in classical coherent communication, in particular for the detection system, which can operate at room temperature and benefits from an easier integration process. In addition to this, the use of advanced digital signal processing (DSP) techniques developed for classical communication allows for bandwidth-efficient temporal shaping, which optimizes the performance of the CV-QKD system. These techniques applied to the detected signal are also fundamental for using a locally generated local oscillator, correcting frequency and phase differences using frequency-multiplexed pilots generated by the transmitter. In this presentation, we will describe how these DSP techniques can be applied to a CV-QKD system and show some recent experimental results obtained by our research group, including results for a receiver based on a Photonic Integrated Circuit (PIC).

CV-QKD Receiver Platform Based On A Silicon Photonic Integrated Circuit

Sun, 05 Mar 2023 00:00:00 +0000

We report on the characterization of a SiGe PIC-based receiver along with its usage in a Gaussian-modulated coherent state CV-QKD setup. Excess noise measurements lead to secret key rate estimations of 280 kbit/s at 6.9 km.

InP-based CV-QKD PIC Transmitter

Sun, 05 Mar 2023 00:00:00 +0000

An InP-based photonic integrated circuit (PIC) transmitter for pulsed Gaussian-modulated coherent-state (GMCS) CV-QKD protocol is presented and characterized. Results show potential asymptotic secret key rates of 0.4 Mbps at 11 km, and up to 2.3 Mbps in back-to-back configuration.

CV-QKD Receiver Platform Based On A Silicon Photonic Chip

Wed, 16 Nov 2022 00:00:00 +0000

A Versatile PIC-based CV-QKD receiver

Wed, 05 Oct 2022 00:00:00 +0000

A Versatile PIC-based CV-QKD Receiver

Mon, 29 Aug 2022 00:00:00 +0000

ParisRegionQCI: A Parisian Quantum Network

Mon, 29 Aug 2022 00:00:00 +0000

A Versatile CV-QKD system with a PIC-based receiver

Mon, 11 Jul 2022 00:00:00 +0000

A versatile and high-performance PIC-based CV-QKD receiver

Wed, 03 Nov 2021 00:00:00 +0000