Tunable Multimode Plasmon–Exciton Coupling for Absorption-Induced Transparency and Strong Coupling

• Published in: Journal of physical chemistry. C 2020-10, Vol.124 (43), p.23888-23894
• Main Authors: Li, Xiaomiao, Liu, Famin, Tian, Menghan, Zhong, Xiaolan
• Format: Article
• Language: English
• Subjects: C: Plasmonics; Optical, Magnetic, and Hybrid Materials
• ISSN: 1932-7447; 1932-7455
• DOI: 10.1021/acs.jpcc.0c08240

The interaction between plasmons and molecular excitons, which can usher in a wide range of novel results under both an electronic and a vibrational strongly coupled state, has attracted great interest over the past decade. Motivated by biosensing detection and chemical property manipulation, the formation mechanism of coupled hybrid polaritons must be demonstrated. Here, several effects based on the interaction between multiple plasmonic modes and a single molecular exciton have been identified using a classic oscillator coupled model. The relationships among the absorption-induced transparency (AIT) effect, Fano interference, and strong coupling are quantificationally analyzed by this model. We find that the dominant mode of conversion from AIT to a strong coupling effect is the plasmonic mode, which depends on the structural period of the plasmonic structure. Furthermore, through optimization of the molecular absorbance, the Rabi splitting is modulated to a maximum of 663 meV and the effective coupling strength reaches up to 0.316. This research paves the way to enhancing the coupling strength and utilizing induced transparency for nanolasing and sensing devices in future applied fields.