Projet de recherche doctoral numero :8567

Description

Date depot: 28 juillet 2023
Titre: Démonstration d’avantage quantique pour des protocoles réseau avec des ressources photoniques pratiques
Directrice de thèse: Eleni DIAMANTI (LIP6)
Domaine scientifique: Sciences et technologies de l'information et de la communication
Thématique CNRS : Systèmes et réseaux

Resumé: The thesis is situated in the field of quantum information and in particular quantum communication networks. The goal of such networks is to provide fundamentally new technology by enabling quantum communication between distant parties, eventually leading to a Quantum Internet. Such networks allow the transmission of quantum bits (qubits) over long distances in order to solve tasks that are provably impossible for any classical communication network. Possibly the most well-known protocol is quantum key distribution, which enables secure communication; but, quantum communication is also known to offer significant advantages for many other tasks. Moreover, the ability to generate entanglement between distant sites provides scientists with a unique new platform for fundamental studies of nature. Photonic resources will be at the heart of the quantum network infrastructure as they provide the optimal means for communication between the network nodes. In this thesis, we will leverage the experimental quantum photonics platform that has been developed in the QI LIP6 group lab in the past few years, to demonstrate a practical advantage for advanced quantum networking tasks. At the heart of this platform is the generation of multipartite polarization-encoded entangled states with high brightness and high fidelity. State-of-the-art superconducting nanowire single-photon detectors are also available in the lab. Starting from these building blocks, in this thesis we will advance towards adding the capability of performing Bell state measurements and we will also examine the generation of a larger class of entangled states than the well-known GHZ states currently available, namely linear graph states. We will also explore the possibility of increasing the dimension of the generated states by exploiting a compact layered technique pioneered in the group. These enhanced experimental resources will be used to implement complex quantum information protocols that require correlations between multiple parties in a network configuration, such as authenticated teleportation and electronic voting. In each case, the implementation will be accompanied by a rigorous theoretical analysis for proving the obtained advantage in security or privacy. We will also seek to perform fundamental physics tests with the goal of refuting communication-assisted local hidden variable models for so-called inflated graph states, with potential applications to distributed computing. We expect that the outcome of this thesis will enlarge considerably the resources and protocols available for the emerging Quantum Internet.



Doctorant.e: Laurent-Puig Nicolas