Engineering topological exciton structures in two-dimensional semiconductors by a periodic electrostatic potential

Abstract

<p>We show the ability of hybridizing different Rydberg states by a periodic electrostatic potential provides a conceptual scheme for engineering topological exciton structures in layered transition metal dichalcogenides. Such a potential can be remotely imprinted from charge distributions in substrate layers, whose large tunability gives rise to rich topological phase diagrams for the exciton. We find the topological lowest band of the dipolar interlayer exciton can exhibit a small bandwidth, as well as remarkable quantum geometries well suited for realizing the long-sought bosonic fractional Chern insulator. For monolayer excitons, topological bands and in-gap helical edge states can emerge near the energy of 2⁢𝑝 states.<br></p>