Parquet renormalization group analysis of weak-coupling instabilities with multiple high-order Van Hove points inside the Brillouin zone
Yu‐Ping Lin, Rahul Nandkishore
Abstract
The discovery of unconventional superconductivity and correlated insulators in twisted bilayer graphene has triggered enormous interest in modern condensed matter research. Here, the authors investigate the potential weak-coupling instabilities in such a system, particularly at the higher-order Van Hove singularity. An asymptotically exact renormalization group analysis uncovers a host of unconventional correlated phases. These include chiral and helical superconductivities, ferromagnetism, and valley-polarized order with potential rotation symmetry breaking. The results may serve as interesting indications for the experimentally observed correlated phases in twisted bilayer graphene.
Topics & Concepts
Van Hove singularityCondensed matter physicsPhysicsRenormalization groupBrillouin zoneBilayer grapheneOrder (exchange)SingularityInstabilityCoupling (piping)RenormalizationQuantum mechanicsGrapheneMaterials scienceMathematicsElectronMathematical analysisFermi levelMetallurgyEconomicsFinancePhysics of Superconductivity and MagnetismQuantum and electron transport phenomenaGraphene research and applications