Superconductivity and Charge Order in Twisted Bilayer Graphene

Our research group investigates emergent quantum phenomena in strongly correlated materials. One of our main research directions is twisted bilayer graphene (TBG), a system that, at so‑called magic angles, develops flat low‑energy bands which enable the formation of correlated insulating phases and unconventional superconductivity.

Theoretical Modeling of Moiré Systems

• Examination of low‑energy effective models for TBG based on Wannier orbitals and moiré superlattices
• Analysis of symmetry properties of pairing operators in honeycomb and moiré lattices
• Study of competing phases including superconductivity, charge density waves, and antiferromagnetism

Computational Method Development

• Application of Cluster Dynamical Mean‑Field Theory (CDMFT) and Variational Cluster Approximation (VCA) to capture strong correlation effects
• Use of Green’s functions and Lanczos algorithms for spectral and ground‑state calculations
• Evaluation of the Potthoff functional to compare the stability of different quantum phases

Long‑Term Objectives

• Establishment of a general computational framework for moiré materials and flat‑band systems
• Extension of methods to other two‑dimensional strongly correlated materials beyond graphene
• Contribution to a deeper understanding of quantum phases in condensed matter physics