Valley splitter and transverse valley focusing in twisted bilayer graphene

Publikation: Beitrag in Fachzeitschrift › Artikel › Forschung › Peer-Review

Autoren

  • Christophe De Beule
  • Peter G. Silvestrov
  • Ming Hao Liu
  • Patrik Recher

Externe Organisationen

  • Technische Universität Braunschweig
  • National Cheng Kung University
  • Laboratory for Emerging Nanometrology Braunschweig (LENA)
Forschungs-netzwerk anzeigen

Details

OriginalspracheEnglisch
Aufsatznummer043151
FachzeitschriftPhysical Review Research
Jahrgang2
Ausgabenummer4
PublikationsstatusVeröffentlicht - 28 Okt. 2020
Extern publiziertJa

Abstract

We study transport in twisted bilayer graphene and show that electrostatic barriers can act as valley splitters, where electrons from the K (K′) valley are transmitted only to, e.g., the top (bottom) layer, leading to valley-layer locked currents. We show that such a valley splitter is obtained when the barrier varies slowly on the moiré scale and induces a Lifshitz transition across the junction, i.e., a change in the Fermi-surface topology. Furthermore, we show that for a given valley the reflected and transmitted current are transversely deflected, as time-reversal symmetry is effectively broken in each valley separately, resulting in valley-selective transverse focusing at zero magnetic field.

ASJC Scopus Sachgebiete

Zitieren

Valley splitter and transverse valley focusing in twisted bilayer graphene. / De Beule, Christophe; Silvestrov, Peter G.; Liu, Ming Hao et al.
in: Physical Review Research, Jahrgang 2, Nr. 4, 043151, 28.10.2020.

Publikation: Beitrag in Fachzeitschrift › Artikel › Forschung › Peer-Review

De Beule, C, Silvestrov, PG, Liu, MH & Recher, P 2020, 'Valley splitter and transverse valley focusing in twisted bilayer graphene', Physical Review Research, Jg. 2, Nr. 4, 043151. https://doi.org/10.1103/PhysRevResearch.2.043151
De Beule, C., Silvestrov, P. G., Liu, M. H., & Recher, P. (2020). Valley splitter and transverse valley focusing in twisted bilayer graphene. Physical Review Research, 2(4), Artikel 043151. https://doi.org/10.1103/PhysRevResearch.2.043151
De Beule C, Silvestrov PG, Liu MH, Recher P. Valley splitter and transverse valley focusing in twisted bilayer graphene. Physical Review Research. 2020 Okt 28;2(4):043151. doi: 10.1103/PhysRevResearch.2.043151
De Beule, Christophe ; Silvestrov, Peter G. ; Liu, Ming Hao et al. / Valley splitter and transverse valley focusing in twisted bilayer graphene. in: Physical Review Research. 2020 ; Jahrgang 2, Nr. 4.
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AU - De Beule, Christophe

AU - Silvestrov, Peter G.

AU - Liu, Ming Hao

AU - Recher, Patrik

N1 - Publisher Copyright: © 2020 authors. Published by the American Physical Society.

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