Tunable intrinsic strong light-matter coupling in transition metal dichalcogenide nanoresonators

Self-hybridizing structures based on transition metal dichalcogenides (TMDCs) are becoming promising candidates for the study of an intrinsic strong light-matter coupling because of the efficient mode overlap with much simplified geometries. However, realizing flexible tuning of intrinsic strong coupling in such TMDC-based structures is still challenging. Here, we propose a strategy for flexible tuning of the intrinsic strong light-matter coupling based on a bulk TMDC material. We report the first demonstration of the strong coupling of intrinsic excitons to whispering gallery modes (WGMs) supported by an all-TMDC nanocavity. Importantly, by simply controlling angles of incidence, a selective excitation of WGMs and an anapole can be realized, which enables a direct modulation of self-hybridized interactions from a bright WGM-exciton coupling to a dark anapole-exciton coupling. Our work is expected to provide unique opportunities for engineering a strong light-matter coupling and to open exciting avenues for highly integrated novel nanophotonic devices.