Condensed Matter Seminars

Quantum phases such as superconductivity and ferromagnetism are among the most important topics in condensed matter physics research. Recently, a family of two-dimensional flat band systems, including magic-angle twisted graphene, uncovered an abundance of symmetry breaking and novel quantum phases.

In this talk, I will introduce the recent advances in these materials and give two examples of how we engineered and revealed new quantum phases of matter in twisted graphene. These include an orbital ferromagnetic state induced by spin-orbit coupling and a zero-field superconducting diode effect. Towards the end of the talk, I will mention our on-going effort of studying a new type of Coulomb-driven rotational symmetry breaking state in the moiré-less bilayer graphene. These examples establish the two-dimensional flat band systems as a versatile platform with multiple tuning knobs, where new physics emerges from the interplay between various quantum phases.