Conductance quantization suppression in the quantum Hall regime.

Autor: Caridad JM; Center for Nanostructured Graphene (CNG), Department of Micro- and Nanotechnology, Technical University of Denmark, 2800, Kongens Lyngby, Denmark. jcar@nanotech.dtu.dk., Power SR; Center for Nanostructured Graphene (CNG), Department of Micro- and Nanotechnology, Technical University of Denmark, 2800, Kongens Lyngby, Denmark.; Catalan Institute of Nanoscience and Nanotechnology (ICN2), CSIC and The Barcelona Institute of Science and Technology, Campus UAB, Bellaterra, Barcelona, 08193, Spain.; Universitat Autònoma de Barcelona, Bellaterra (Cerdanyola del Vallès), 08193, Spain., Lotz MR; Center for Nanostructured Graphene (CNG), Department of Micro- and Nanotechnology, Technical University of Denmark, 2800, Kongens Lyngby, Denmark., Shylau AA; Center for Nanostructured Graphene (CNG), Department of Micro- and Nanotechnology, Technical University of Denmark, 2800, Kongens Lyngby, Denmark., Thomsen JD; Center for Nanostructured Graphene (CNG), Department of Micro- and Nanotechnology, Technical University of Denmark, 2800, Kongens Lyngby, Denmark., Gammelgaard L; Center for Nanostructured Graphene (CNG), Department of Micro- and Nanotechnology, Technical University of Denmark, 2800, Kongens Lyngby, Denmark., Booth TJ; Center for Nanostructured Graphene (CNG), Department of Micro- and Nanotechnology, Technical University of Denmark, 2800, Kongens Lyngby, Denmark., Jauho AP; Center for Nanostructured Graphene (CNG), Department of Micro- and Nanotechnology, Technical University of Denmark, 2800, Kongens Lyngby, Denmark., Bøggild P; Center for Nanostructured Graphene (CNG), Department of Micro- and Nanotechnology, Technical University of Denmark, 2800, Kongens Lyngby, Denmark. peter.boggild@nanotech.dtu.dk.
Jazyk: angličtina
Zdroj: Nature communications [Nat Commun] 2018 Feb 13; Vol. 9 (1), pp. 659. Date of Electronic Publication: 2018 Feb 13.
DOI: 10.1038/s41467-018-03064-8
Abstrakt: Conductance quantization is the quintessential feature of electronic transport in non-interacting mesoscopic systems. This phenomenon is observed in quasi one-dimensional conductors at zero magnetic field B, and the formation of edge states at finite magnetic fields results in wider conductance plateaus within the quantum Hall regime. Electrostatic interactions can change this picture qualitatively. At finite B, screening mechanisms in narrow, gated ballistic conductors are predicted to give rise to an increase in conductance and a suppression of quantization due to the appearance of additional conduction channels. Despite being a universal effect, this regime has proven experimentally elusive because of difficulties in realizing one-dimensional systems with sufficiently hard-walled, disorder-free confinement. Here, we experimentally demonstrate the suppression of conductance quantization within the quantum Hall regime for graphene nanoconstrictions with low edge roughness. Our findings may have profound impact on fundamental studies of quantum transport in finite-size, two-dimensional crystals with low disorder.
Databáze: MEDLINE
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