Fan Wu, Jiaqi Guo, Yuming Huang, Kun Liang, Lei Jin, Junqiang Li, Xuyan Deng, Rongzhen Jiao, Yumin Liu, Jiasen Zhang, Wei Zhang, Li Yu
Author Information
Fan Wu: State Key Laboratory of Information Photonics and Optical Communications, School of Science, Beijing University of Posts and Telecommunications, 10 Xitucheng Road, Beijing 100876, China. ORCID
Jiaqi Guo: State Key Laboratory of Information Photonics and Optical Communications, School of Science, Beijing University of Posts and Telecommunications, 10 Xitucheng Road, Beijing 100876, China.
Yuming Huang: State Key Laboratory of Information Photonics and Optical Communications, School of Science, Beijing University of Posts and Telecommunications, 10 Xitucheng Road, Beijing 100876, China.
Kun Liang: State Key Laboratory of Information Photonics and Optical Communications, School of Science, Beijing University of Posts and Telecommunications, 10 Xitucheng Road, Beijing 100876, China. ORCID
Lei Jin: State Key Laboratory of Information Photonics and Optical Communications, School of Science, Beijing University of Posts and Telecommunications, 10 Xitucheng Road, Beijing 100876, China.
Junqiang Li: State Key Laboratory of Information Photonics and Optical Communications, School of Science, Beijing University of Posts and Telecommunications, 10 Xitucheng Road, Beijing 100876, China.
Xuyan Deng: State Key Laboratory of Information Photonics and Optical Communications, School of Science, Beijing University of Posts and Telecommunications, 10 Xitucheng Road, Beijing 100876, China.
Rongzhen Jiao: State Key Laboratory of Information Photonics and Optical Communications, School of Science, Beijing University of Posts and Telecommunications, 10 Xitucheng Road, Beijing 100876, China.
Yumin Liu: State Key Laboratory of Information Photonics and Optical Communications, School of Science, Beijing University of Posts and Telecommunications, 10 Xitucheng Road, Beijing 100876, China. ORCID
Jiasen Zhang: State Key Laboratory for Mesoscopic Physics and Department of Physics, Peking University, Beijing 100871, China. ORCID
Wei Zhang: Institute of Applied Physics and Computational Mathematics, Beijing 100088, China. ORCID
Li Yu: State Key Laboratory of Information Photonics and Optical Communications, School of Science, Beijing University of Posts and Telecommunications, 10 Xitucheng Road, Beijing 100876, China.
Understanding the unique characteristics of plexcitons, hybridized states resulting from the strong coupling between plasmons and excitons, is vital for both fundamental studies and practical applications in nano-optics. However, the research of plexcitons from the perspective of chiral optics has been rarely reported. Here, we experimentally investigate the optical chirality of plexcitonic systems consisting of composite metal nanoparticles and chiral J-aggregates in the strong coupling regime. Mode splitting and anticrossing behavior are observed in both the circular dichroism (CD) and extinction spectra of the hybrid nanosystems. A large mode splitting (at zero detuning) of up to 136 meV/214 meV in CD/extinction measurements confirms that the systems attain the strong coupling regime. This phenomenon indicates that the formation of plexcitons modifies not only the extinction but also the optical chirality of the hybrid systems. We develop a quasistatic theory to elucidate the chiral optical responses of hybrid systems. Furthermore, we propose and justify a criterion of strong plasmon-exciton interaction: the mode splitting in the CD spectra (at zero detuning) is larger than half of that in the extinction spectra. Our findings give a chiral perspective on the study of strong plasmon-exciton coupling and have potential applications in the chiral optical field.
