Strong coupling of Fabry-Pérot cavity mode, anapole, and exciton supported by an optical cavity with heterogeneous nano-optical metasurfaces

Carefully designed metasurfaces can serve as effective platforms for strong coupling phenomena by the excitation of specific modes and the enhancement of light-matter interactions. However, strong coupling simultaneously involving Fabry-P\'erot (FP) cavity modes, anapole states, and excitons has not been thoroughly explored. In this work, we numerically present the strong coupling of a FP cavity-anapole-exciton supported by a nano-optical metasurface of bulk WS₂-Si heterogeneous nanodisks inserted into a FP optical cavity. The excited multiorder FP cavity modes enable giant Rabi splittings with tunable population due to all generated odd-order FP cavity modes strongly coupling with the anapole state and exciton of bulk WS₂-Si heterogeneous nanodisks. Giant Rabi splittings of 643 and 335 meV are, respectively, achieved by the first-order FP and third-order FP cavity-anapole-exciton interactions. Our designed hybrid system provides a robust platform for exploring ultrahigh Rabi splittings and strong coupling of multiple optical responses in light-matter interactions.