PROJECT
Quantum cryptographic schemes for quantum networks
DOCTORAL CANDIDATE
Supervisors
Curty (UVIGO), Razavi (ULEEDS), Azuma (NTT), Tamaki (UT), Majenz (DTU).
Objectives
Designing efficient multi-user quantum cryptographic schemes for entanglement-based quantum networks.
Expected Results
Proposals for quantum cryptographic schemes with multiple users over quantum networks. Performance and security analysis of such schemes in a practical setting.
Description
Most quantum cryptographic schemes assume a two-user setting in a point-to-point network configuration, which do not fully exploit the richness of complex quantum networks. Moreover, to extend the achievable distance between end users, they typically rely on the use of trusted nodes. A principal goal of this project is to design efficient quantum cryptographic schemes—such as e.g. those achieving conference key agreement or distributed quantum computing—for various entanglement-based quantum network topologies with multiple users and untrusted nodes, and evaluate their security in a practical setting. Moreover, we shall investigate their performance and robustness against typical device imperfections of the users’ apparatuses, as well as those of the untrusted networks nodes.
Methodology
The Doctoral Candidate will study conference key agreement and beyond QKD multi-user cryptographic schemes suitable for entanglement-based quantum networks. Efficient techniques to establish different kinds of entanglement between the end users will be explored. The security and robustness of the designed schemes against side-channels will be investigating by adapting known QKD methods to this scenario.
Risks
If obtaining analytical results turn out to be too complex to achieve, or they provide loose security bounds, numerical methods will be used. If a quantum cryptographic scheme does not provide advantages over classical solutions, or over a combination of multiple two-users setups, alternative schemes will be considered.
