Description du projet
Démasquer les phénomènes quantiques exotiques dans les matériaux tordus
La surprenante émergence d’une supraconductivité non conventionnelle et d’états isolants corrélés par la simple torsion d’une feuille de carbone a ravivé l’intérêt d’une étude plus approfondie des propriétés des matériaux moirés. L’étude de la façon dont des angles spécifiques dans ces matériaux peuvent modifier leurs propriétés électriques constitue un nouveau sous-domaine de la science des matériaux connu sous le nom de twistronique. Par ailleurs, la possibilité de contrôler les vibrations par torsion donne naissance à la twistnonique. Financé par le programme Actions Marie Skłodowska-Curie, le projet ComEPT entend combiner la twistronique et la twistnonique pour répondre à des questions issues d’observations expérimentales qui ne sont guère comprises. La compréhension détaillée des interactions électron-phonon dans les matériaux moirés devrait permettre de contrôler des phénomènes quantiques exotiques.
Objectif
The recent discovery of correlated insulating states and unconventional superconductivity in twisted bilayer graphene triggered an intense research effort to understand the properties of moiré materials. The ability to manipulate electronic properties through the twist angle between two two-dimensional materials has given rise to the new field of twistronics. Besides novel electronic properties, moiré materials also feature unconventional vibrational properties, such as novel phason modes. The ability to control vibrations by twisting gives rise to the new field of twistnonics.
Despite much progress, many experimental observations in moiré materials are not yet well understood. For example, the microscopic origin of the “strange” metal phase with a resistivity which is linear in temperature and the nature of pairing glue that induces superconductivity are hotly debated. To answer these questions, I propose to combine the fields of twistronics and twistnonics and study the role of electron-phonon interactions in twisted bilayer materials. Specifically, I plan to
+ develop a computational framework to study electron-phonon interactions in moiré materials. Because of the large unit cells of moiré materials, standard implementations of this approach cannot be used. To overcome this challenge, I will combine force-field approaches for phonons with tight-binding methods for electrons and develop a new parallelized computer code.
+ understand electron transport experiments in different twisted bilayer materials, including twisted bilayer transition metal dichalcogenides and twisted bilayer graphene.
+ study the electron-phonon mediated superconductivity in twisted bilayer materials.
The results of these calculations will enable a detailed understanding of the interactions between electrons and phonons in moiré materials and enable the control of exotic quantum phenomena with the twist angles.
Champ scientifique
Mots‑clés
Programme(s)
Régime de financement
MSCA-IF - Marie Skłodowska-Curie Individual Fellowships (IF)Coordinateur
SW7 2AZ LONDON
Royaume-Uni