Valley-symmetry-preserved transport in ballistic graphene with gate-defined carrier guiding
SCIE
SCOPUS
- Title
- Valley-symmetry-preserved transport in ballistic graphene with gate-defined carrier guiding
- Authors
- Kim, M; Choi, JH; Lee, SH; Watanabe, K; Taniguchi, T; Jhi, SH; LEE, HU JONG
- Date Issued
- 2016-11
- Publisher
- NATURE PUBLISHING GROUP
- Abstract
- Ever since the discovery of graphene(1), valley symmetry and its control(2,3) in the material have been a focus of continued studies in relation to valleytronics(4,5). Carrier-guiding quasi-one-dimensional (1D) graphene nanoribbons (GNRs)(6-12) with quantized energy subbands preserving the intrinsic Dirac nature have provided an ideal system to that end. Here, by guiding carriers through dual-gate operation in high-mobility monolayer graphene, we report the realization of quantized conductance in steps of 4e(2)/h in zero magnetic field, which arises from the full symmetry conservation of quasi-1D ballistic GNRs with effective zigzag-edge conduction. A tight-binding model calculation confirms conductance quantization corresponding to zigzag-edge conduction even for arbitrary GNR orientation. Valley-symmetry conservation is further confirmed by intrinsic conductance interference with a preserved Berry phase of pi in a graphene-based Aharonov-Bohm(AB) ring preparedby similar dualgating. This top-down approach for gate-defined carrier guiding in ballistic graphene is of particular relevance in the efforts towards efficient and promising valleytronic applications.
- URI
- https://oasis.postech.ac.kr/handle/2014.oak/38012
- DOI
- 10.1038/NPHYS3804
- ISSN
- 1745-2473
- Article Type
- Article
- Citation
- NATURE PHYSICS, vol. 12, no. 11, page. 1022 - +, 2016-11
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- There are no files associated with this item.
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