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Abstract Tunable Fano resonances and plasmon–exciton coupling are demonstrated at room temperature in hybrid systems consisting of single plasmonic nanoparticles deposited on top of the transition metal dichalcogenide monolayers. By using single Au nanotriangles (AuNTs) on monolayer WS2as model systems, Fano resonances are observed from the interference between a discrete exciton band of monolayer WS2and a broadband plasmonic mode of single AuNTs. The Fano lineshape depends on the exciton binding energy and the localized surface plasmon resonance strength, which can be tuned by the dielectric constant of surrounding solvents and AuNT size, respectively. Moreover, a transition from weak to strong plasmon–exciton coupling with Rabi splitting energies of 100–340 meV is observed by rationally changing the surrounding solvents. With their tunable plasmon–exciton interactions, the proposed WS2–AuNT hybrids can open new pathways to develop active nanophotonic devices.
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This content will become publicly available on May 19, 2026
Fano Resonance in Ion-Bombarded Au-SiO2 Nanocomposites: Analysis of Mode Coupling and Optical Properties
This study investigates the optical properties of ion-bombarded Au-SiO2 nanocomposites, focusing on the enhanced Fano resonance observed in these samples. The formation of nanocrystals and nanocavities due to ion bombardment leads to significant interactions between plasmonic and vibrational modes, resulting in pronounced Fano resonance in the strong coupling regime. The study aims to explain the closer spacing of modes, the elevated baseline absorbance, and the asymmetric lineshape observed in the ion-bombarded samples. A detailed analysis is provided, comparing these findings with other sample preparations, such as Au-coated SiO2 and 20 nm Au colloidal on SiO2. The implications of these results for understanding plasmonic behavior and their potential applications in nanophotonics are discussed.
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- Award ID(s):
- 2331969
- PAR ID:
- 10591681
- Publisher / Repository:
- MDPI
- Date Published:
- Journal Name:
- Coatings
- Volume:
- 15
- Issue:
- 5
- ISSN:
- 2079-6412
- Page Range / eLocation ID:
- 605
- Subject(s) / Keyword(s):
- plasmon FTIR nanoparticles
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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