Description du sujet de thèse

The coherence time is a key metric for evaluating the performance of a quantum bit. We have recently proposed a new type of qubit that stores information in the mechanical displacement of a carbon nanotube and leverages its coupling to an electronic two-level system to induce sufficiently strong anharmonicity, enabling its manipulation and readout.
In this PhD project, we aim to study the coupling between the mechanical modes of suspended bilayer graphene and the quantum dots that can be formed within it. Bilayer graphene offers a remarkable advantage over monolayer graphene: it allows for the precise design of quantum dots while retaining the exceptional mechanical properties of graphene. The electronic structure of bilayer graphene has been intensively studied in recent years, revealing a rich internal physics with valley and spin degrees of freedom. It has been demonstrated that qubits with extremely long lifetimes, reaching up to 30 seconds, can be observed in this system. However, their manipulation remains a major challenge.
This thesis will theoretically explore how the deformation of a mechanical oscillator can be exploited to create new mechanical qubits. Collaborations with experimental groups that will study a physical realization of the qubit will be part of the project.

Contexte de travail

This project is part of the European program HORIZON-EIC-2025-PATHFINDEROPEN MECH-QUBIT (MECHanical QUBIT With Enhanced Coherence), conducted in close collaboration with the experimental teams of Adrian Bachtold (ICFO, Spain) and Christoph Stampfer (RWTH Aachen, Germany). The successful candidate will join the Laboratoire Ondes et Matière d'Aquitaine (LOMA) in Bordeaux, within the condensed matter theory team. This dynamic environment includes several researchers working on related topics in quantum technologies, providing a stimulating scientific framework ideal for exploring synergies between theory and experiment in this innovative field.

Le poste se situe dans un secteur relevant de la protection du potentiel scientifique et technique (PPST), et nécessite donc, conformément à la réglementation, que votre arrivée soit autorisée par l'autorité compétente du MESR.

Contraintes et risques

N.A.

Informations complémentaires

The ideal candidate will hold (or will hold soon) a master's degree in physics, preferably with experience in condensed matter theory or quantum optics. A strong interest in deeply understanding physical phenomena, along with curiosity about the theoretical challenges in quantum technologies, will be major assets for this project. Openness to close collaboration with experimental teams will further complement this profile.
The contract start date is flexible and can be postponed until September or October 2026, depending on the needs of the selected candidate.