Strong Coupling at Room Temperature Achieved by Nanoscale Inverse Design

Room-temperature strong coupling between plasmonic nanocavities and monolayer semiconductors is a prominent path toward efficient, integrated devices. However, designing such systems is challenging due to the nontrivial dependence of the strong coupling on the properties of both the cavity and the emitter, as well as the subwavelength scale of interaction. In this work, we develop a general methodology for obtaining strongly coupled hybrid metasurfaces consisting of plasmonic nanocavities coupled to atomically thin semiconductor layers, exhibiting extreme values of Rabi splitting, by inverse design of the near-field plasmonic response. We experimentally demonstrate large values of Rabi splitting in a nanoantenna design while providing theoretically optimal configurations for additional types of nanostructures. Our results open a path to maximizing light-matter interactions in integrated platforms for classical and quantum-optical applications.