The HADES seminar on Tuesday, February 4th, will be at 3:00pm in Room 740 (UNUSUAL TIME).

Speaker: Mengxuan Yang

Abstract: Magic angles are a hot topic in condensed matter physics: when two sheets of graphene are twisted by those angles, the resulting material is superconducting. In 2011, Bistritzer and MacDonald proposed a model that is experimentally very accurate in predicting magic angles. In this talk, I will introduce some recent mathematical progress on the Bistritzer–MacDonald Hamiltonian, including the generic existence of Dirac cones and the mathematical characterization of magic angles. I will also discuss topological aspects of this model, as well as some new mathematical discoveries in twisted multilayer graphene.