| Autor: |
Ye Y; Department of Materials Science and Engineering, University of Washington, Seattle, Washington 98195, United States., Qian J; Department of Materials Science and Engineering, University of Washington, Seattle, Washington 98195, United States., Zhang XW; Department of Materials Science and Engineering, University of Washington, Seattle, Washington 98195, United States., Wang C; Department of Materials Science and Engineering, University of Washington, Seattle, Washington 98195, United States., Xiao D; Department of Materials Science and Engineering, University of Washington, Seattle, Washington 98195, United States.; Department of Physics, University of Washington, Seattle, Washington 98195, United States., Cao T; Department of Materials Science and Engineering, University of Washington, Seattle, Washington 98195, United States. |
| Abstrakt: |
In this paper, we discuss a new moiré system where the long moiré periodicity emerges from two dissimilar van der Waals layers with vastly different lattice constants. We reconstruct the first layer using a 3 by 3 supercell resembling the Kekulé distortion in graphene, and such reconstruction becomes nearly commensurate with the second layer. We term this construction a Kekulé moiré superlattice, which enables coupling between moiré bands from remote valleys in momentum space. Kekulé moiré superlattices can be realized in heterostructures of transition metal dichalcogenides and metal phosphorus trichalcogenides such as MoTe 2 /MnPSe 3 . By first-principles calculations, we demonstrate that the antiferromagnetic MnPSe 3 strongly couples the otherwise degenerate Kramers' valleys of MoTe 2 , resulting in valley pseudospin textures that depend on the Néel vector direction, stacking geometry, and external fields. With one hole per moiré supercell, the system becomes a Chern insulator with highly tunable topological phases. |
