Year: 2021
Type: article
Abstract: The quantum Hall effect is the seminal example of topological protection, as charge carriers are transmitted through one-dimensional edge channels where backscattering is prohibited. Graphene has made its marks as an exceptional platform to reveal new facets of this remarkable property. However, in conventional Hall bar geometries, topological protection of graphene edge channels is found regrettably less robust than in high mobility semi-conductors. Here, we explore graphene quantum Hall regime at the local scale, using a scanning gate microscope. We reveal the detrimental influence of antidots along the graphene edges, mediating backscattering towards upstream edge channels, hence triggering topological breakdown. Combined with simulations, our experimental results provide further insights into graphene quantum Hall channels vulnerability. In turn, this may ease future developments towards precise manipulation of topologically protected edge channels hosted in various types of two-dimensional crystals.
Source: Nature Communications
Authors: N. Moreau, B. Brun, S. Somanchi, K. Watanabe, T. Taniguchi, C. Stampfer, B. Hackens
Language: English
Subfield: Atomic and Molecular Physics, and Optics
Field: Physics and Astronomy
Domain: Physical Sciences
Open Access status: gold
Estimated APC paid: $5,560
Funders: Waalse Gewest, European Commission, Deutsche Forschungsgemeinschaft, Agence Nationale de la Recherche, Ministry of Education, Culture, Sports, Science and Technology, Fonds De La Recherche Scientifique - FNRS, Japan Society for the Promotion of Science, Fonds pour la Formation à la Recherche dans l’Industrie et dans l’Agriculture, Core Research for Evolutional Science and Technology
Awards: G1111125796, G1294209642, Graphene-based disruptive technologies, TunAble Twistronics: local tuning and probing of TOpOlogical edge states and Superconductivity in bilayer graphene, G1987423430, G2479918313, G2575309732, G2779214953, G2868987701, G3406638862, G3510308925, G353390944, G369169853, G434337789, G4636866504, G4703715196, Graphene Flagship Core Project 2, G6415085478, G6718509927, G7177903685, G7664062879, G7879866177, G8538630060, G8572835978
OpenAlex ID: W3093982817