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Signatures of single quantum dots in graphene nanoribbons within the quantum Hall regime.

ABSTRACT: We report on the observation of periodic conductance oscillations near quantum Hall plateaus in suspended graphene nanoribbons. They are attributed to single quantum dots that are formed in the narrowest part of the ribbon, in the valleys and hills of a disorder potential. In a wide flake with two gates, a double-dot system's signature has been observed. Electrostatic confinement is enabled in single-layer graphene due to the gaps that are formed between the Landau levels, suggesting a way to create gate-defined quantum dots that can be accessed with quantum Hall edge states.

SUBMITTER: Tovari E

PROVIDER: S-EPMC5315012 | biostudies-literature | 2016 Jun

REPOSITORIES: biostudies-literature

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Signatures of single quantum dots in graphene nanoribbons within the quantum Hall regime.

Tóvári Endre E Makk Péter P Rickhaus Peter P Schönenberger Christian C Csonka Szabolcs S

Nanoscale 20160601 22

We report on the observation of periodic conductance oscillations near quantum Hall plateaus in suspended graphene nanoribbons. They are attributed to single quantum dots that are formed in the narrowest part of the ribbon, in the valleys and hills of a disorder potential. In a wide flake with two gates, a double-dot system's signature has been observed. Electrostatic confinement is enabled in single-layer graphene due to the gaps that are formed between the Landau levels, suggesting a way to cr ...[more]

PMID: 27198562

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