Magic-angle twisted symmetric trilayer graphene as a topological heavy-fermion problem
Jiabin Yu, Ming Xie, B. Andrei Bernevig, S. Das Sarma
Abstract
A topological heavy-fermion (THF) model is formulated for magical-angle twisted symmetric trilayer graphene (MATSTG), where ``symmetric'' means that the top and bottom layers are rotated equally with respect to the middle layer. In addition to the localized $f$ modes and itinerant $c$ modes (which serve as the basis of the THF model for twisted bilayer graphene), the THF model of MATSTG consists of extra Dirac ($d$) modes. The newly proposed $f\ensuremath{-}c\ensuremath{-}d$ THF model can well reproduce previous numerical results on the correlated phases at integer fillings, and can provide a new analytical understanding of them at charge neutrality.
Topics & Concepts
PhysicsBilayer grapheneFermionMagnetic monopoleTopology (electrical circuits)GrapheneQuantum mechanicsCondensed matter physicsCombinatoricsMathematicsGraphene research and applicationsTopological Materials and PhenomenaQuantum and electron transport phenomena