Quantum phases in twisted graphene and Moire profiles

• Applicant: Professor Dr. Felix von Oppen
• Subject Area: Theoretical Condensed Matter Physics ; Experimental Condensed Matter Physics
• Term: since 2021
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 490921351

Twisted layers of graphene (twisted bilayer graphene) form extremely flat bands and exhibit a fascinating abundance of quantum phases. Experimentally, one observes - near a magic angle and within a narrow range of densities - correlated insulators, Chern insulators, superconductivity, ferromagnetism, and other phases. Due to the flat bands, the electronic interactions are effectively strongly enhanced in twisted graphene. On the one hand, this underlies the many correlated phases, on the other hand, this is a challenge for their theoretical description. The central goal of this project is to develop a comprehensive theoretical understanding of the phase diagram and the physics of twisted graphene. We will emphasize superconducting and symmetry-breaking insulator phases. Beginning with bilayers, we will also consider trilayers as well as other multi-layer systems, which exhibit similar phase diagrams. We will specifically propose experimental signatures, which contribute to a better characterization of the observed ordering phenomena.

• DFG Programme: Research Grants
• International Connection: France
• Cooperation Partners: Professor Dr. Mark Oliver Goerbig; Professor Christophe Mora; Professorin Dr. Rebeca Ribeiro-Palau