Poster presentation

Valley-polarized edge modes in sliding bilayer graphene
H. Minh Lam¹, D.-H.-Minh Nguyen², Dario Bercioux^2,3, and V. Nam Do¹

1 Department of Basic Science, Phenikaa Institute for Advanced Study (PIAS), A1 Building, Phenikaa University, Hanoi 10000, Vietnam 2 Donostia International Physics Center, 20018 Donostia-San Sebastian, Spain 3 IKERBASQUE, Basque Foundation for Science, Euskadi Plaza, 5, 48009 Bilbao, Spain

Besides the conventional electronic charge and spin, valley degrees of freedom are an additional feature of electrons that can be used to encode and process information [1]. In this work, we theoretically propose that propagating valley-polarized edge states exist in sliding bilayer graphene [2]. For some specific stacking configurations of the bilayer graphene, the Dirac cones of the two layers at a valley are separated and shifted in energy. As a result, the topological edge states connecting the two Dirac points and protected by the winding number have nonzero group velocity, giving rise to propagating edge modes.

Figure 1: A stacking configuration of bilayer graphene that gives rise to valley-polarized edge modes.

[1] J. Schaibley et al., Nat Rev Mater 1, 16055 (2016).
[2] VN Do, Phys. Rev. B 104 205121 (2021).