Edge-mode polariton chains in the dielectric whispering gallery modes and two-dimensional material’s topological system

Abstract

Topological polaritons are a new topological phenomenon that has a combination of advantages such as strong nonlinearity, low effective mass, and topological invariants. However, the actual configurations of topological polaritons based on two-dimensional materials have not been discussed yet. In this paper, we theoretically demonstrate a Su-Schrieffer-Heeger (SSH) model (Sinev et al 2015 Nanoscale 7 11904; Dobrykh et al 2018 Phys. Rev. Lett. 121 163901; Qi et al 2020 Phys. Rev. A 102 022404) with topological polaritons by TiO2 whispering gallery modes and nanodisk arrays coupled with two-dimensional transition metal dichalcogenides (TMDCs) exciton materials. The transverse electric-polarized strong evanescent fields around the TiO2 nanodisks coupled with the TMDCs excitons for each atom can construct strong coupling between exciton-polaritons with a distinct resonant Rabi splitting dispersion of approximately 14 nm. By changing the distance between adjacent nanodisks, we observed obvious edge states for the SSH polariton chain at the wavelength of polaritons. This study paves the way toward new topological polaritons in large nonlinear devices with an edge transport based on two-dimensional materials.