Non-Hermitian Moiré Valley Filter
Loading...
Access rights
openAccess
Journal Title
Journal ISSN
Volume Title
A1 Alkuperäisartikkeli tieteellisessä aikakauslehdessä
This publication is imported from Aalto University research portal.
View publication in the Research portal
View/Open full text file from the Research portal
Other link related to publication
View publication in the Research portal
View/Open full text file from the Research portal
Other link related to publication
Date
2024-04-12
Department
Major/Subject
Mcode
Degree programme
Language
en
Pages
7
Series
Physical Review Letters, Volume 132, issue 15, pp. 1-7
Abstract
A valley filter capable of generating a valley-polarized current is a crucial element in valleytronics, yet its implementation remains challenging. Here, we propose a valley filter made of a graphene bilayer which exhibits a 1D moiré pattern in the overlapping region of the two layers controlled by heterostrain. In the presence of a lattice modulation between layers, electrons propagating in one layer can have valley-dependent dissipation due to valley asymmetric interlayer coupling, thus giving rise to a valley-polarized current. Such a process can be described by an effective non-Hermitian theory, in which the valley filter is driven by a valley-resolved non-Hermitian skin effect. Nearly 100% valley polarization can be achieved within a wide parameter range and the functionality of the valley filter is electrically tunable. The non-Hermitian topological scenario of the valley filter ensures high tolerance against imperfections such as disorder and edge defects. Our work opens a new route for efficient and robust valley filters while significantly relaxing the stringent implementation requirements.Description
Keywords
Other note
Citation
Shao, K, Geng, H, Liu, E, Lado, J, Chen, W & Xing, D Y 2024, ' Non-Hermitian Moiré Valley Filter ', Physical Review Letters, vol. 132, no. 15, 156301, pp. 1-7 . https://doi.org/10.1103/PhysRevLett.132.156301