Ferroelectric valley valves with graphene/MoTe2 van der Waals heterostructures

Loading...
Thumbnail Image
Journal Title
Journal ISSN
Volume Title
A1 Alkuperäisartikkeli tieteellisessä aikakauslehdessä
Date
2023-02-02
Major/Subject
Mcode
Degree programme
Language
en
Pages
2181-2187
Series
Nanoscale, Volume 15, issue 5
Abstract
Ferroelectric van der Waals heterostructures provide a natural platform to design a variety of electrically controllable devices. In this work, we demonstrate that AB bilayer graphene encapsulated in MoTe2 acts as a valley valve that displays a switchable built-in topological gap, leading to ferroelectrically driven topological channels. Using a combination of ab initio calculations and low energy models, we show that the ferroelectric order of MoTe2 allows the control of the gap opening in bilayer graphene and leads to topological channels between different ferroelectric domains. Moreover, we analyze the effect that the moiré modulation between MoTe2 and graphene layers has in the topological modes, demonstrating that the edge states are robust against moiré modulations of the ferroelectrically-induced electric potential. Our results put forward ferroelectric/graphene heterostructures as versatile platforms to engineer switchable built-in topological channels without requiring an external electric bias.
Description
Funding Information: We acknowledge the computational resources provided by the Aalto Science-IT project, and the financial support from the Academy of Finland Projects No. 331342, No. 336243 and No. 349696 and the Jane and Aatos Erkko Foundation. We thank. P. Liljeroth, M. Amini and S. Kezilebieke for useful discussions. Publisher Copyright: © 2023 The Royal Society of Chemistry.
Keywords
Other note
Citation
Fumega , A O & Lado , J L 2023 , ' Ferroelectric valley valves with graphene/MoTe 2 van der Waals heterostructures ' , Nanoscale , vol. 15 , no. 5 , pp. 2181-2187 . https://doi.org/10.1039/d2nr05185k