Triple Plexcitonic Nonreciprocity of Magnetochiral Plexcitons.

Nonreciprocal quantum devices, allowing different transmission efficiencies of light-matter polaritons along opposite directions, are key technologies for modern photonics, yet their miniaturization and fine manipulation remain an open challenge. Here, we report on magnetochiral plexcitons dressed with geometric-time double asymmetry in compact nonreciprocal hybrid metamaterials, leading to triple plexcitonic nonreciprocity with flexible controllability. A general magnetically dressed plexcitonic Born-Kuhn model is developed to reveal the hybrid optical nature and dynamic energy evolution of magnetochiral plexcitons, demonstrating a plexcitonic nonreciprocal mechanism originating from the strong coupling among photon, electron, and spin degrees of freedom.

The Mechanism of Manipulating Chirality and Chiral Sensing Based on Chiral Plexcitons in a Strong-Coupling Regime.

Manipulating plasmonic chirality has shown promising applications in nanophotonics, stereochemistry, chirality sensing, and biomedicine. However, to reconfigure plasmonic chirality, the strategy of constructing chiral plasmonic systems with a tunable morphology is cumbersome and complicated to apply for integrated devices. Here, we present a simple and effective method that can also manipulate chirality and control chiral light-matter interactions only via strong coupling between chiral plasmonic nanoparticles and excitons.

Realization of exciton-polariton optical chirality based on strong coupling between intrinsic chiral quasibound states in the continuum and monolayer WS2.

Hybrid quasiparticles produced by the strong interaction between nanostructures and excitons will exhibit optical chirality when one of the coupled components is chiral. Due to the tunability of hybrid states, the coupled system has potential applications in chiral devices and chiral sensing. However, reported chiral materials including chiral molecules and three-dimensional chiral structures in the coupled system limit the application due to the weak chiroptical responses and difficult fabrication, respectively.

The Mechanism and Fine-Tuning of Chiral Plexcitons in the Strong Coupling Regime.

Chiral plexcitons, produced by the strong interaction between plasmonic nanocavities and chiral molecules, can provide a promising direction for controlling chiroptical responses on the nanoscale. Here, we reveal the chiral origin and electromagnetic hybridization process in chiral strongly coupled systems. The mechanism and unique advantages of chiral plexcitons for fine-tuning circular dichroism (CD) responses are demonstrated, providing a rule for controlling chiral light-matter interactions in complex chiral nanosystems.