Integer and fractional quantum anomalous Hall effects in pentalayer graphene
Ming Xie, S. Das Sarma
Abstract
Through a critical analysis of transport data from the recently discovered fractional quantum anomalous Hall effect (FQAHE) in rhombohedral pentalayer graphene on hBN, the authors identify here significant discrepancies between the FQAHE and the conventional fractional quantum Hall effect in Landau levels. Most notably, the excitation gap remains nearly constant for all observed fractions, starkly contrasting with the ``v''-shaped linear dependence on |$\ensuremath{\nu}$-1/2| predicted by the composite fermion model. This uncovers an intriguing puzzle regarding the nature of the FQAHE states.
Topics & Concepts
Quantum Hall effectFractional quantum Hall effectGrapheneInteger (computer science)Condensed matter physicsPhysicsComposite fermionQuantum mechanicsQuantumQuantum spin Hall effectQuantum electrodynamicsMagnetic fieldComputer scienceProgramming languageGraphene research and applicationsQuantum and electron transport phenomenaQuantum Computing Algorithms and Architecture