Signatures of strong coupling on nanoparticles
- In the strong coupling regime, exciton and plasmon excitations are hybridized into combined system excitations. The correct identification of the coupling regime in these systems is currently debated, from both experimental and theoretical perspectives. In this article we show that the extinction spectra may show a large peak splitting, although the energy loss encoded in the absorption spectra clearly rules out the strong coupling regime. We investigate the coupling of J-aggregate excitons to the localized surface plasmon polaritons on gold nanospheres and nanorods by fine-tuning the plasmon resonance via layer-by-layer deposition of polyelectrolytes. While both structures show a characteristic anticrossing in extinction and scattering experiments, the careful assessment of the systems’ light absorption reveals that strong coupling of the plasmon to the exciton is not present in the nanosphere system. In a phenomenological model of two classical coupled oscillators, a Fano-like regime causes only the resonance of the light-drivenIn the strong coupling regime, exciton and plasmon excitations are hybridized into combined system excitations. The correct identification of the coupling regime in these systems is currently debated, from both experimental and theoretical perspectives. In this article we show that the extinction spectra may show a large peak splitting, although the energy loss encoded in the absorption spectra clearly rules out the strong coupling regime. We investigate the coupling of J-aggregate excitons to the localized surface plasmon polaritons on gold nanospheres and nanorods by fine-tuning the plasmon resonance via layer-by-layer deposition of polyelectrolytes. While both structures show a characteristic anticrossing in extinction and scattering experiments, the careful assessment of the systems’ light absorption reveals that strong coupling of the plasmon to the exciton is not present in the nanosphere system. In a phenomenological model of two classical coupled oscillators, a Fano-like regime causes only the resonance of the light-driven oscillator to split up, while the other one still dissipates energy at its original frequency. Only in the strong-coupling limit do both oscillators split up the frequencies at which they dissipate energy, qualitatively explaining our experimental finding.…
Author details: | Felix SteteORCiD, Wouter-Willem Adriaan KoopmanORCiDGND, Matias BargheerORCiDGND |
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DOI: | https://doi.org/10.1021/acsphotonics.7b00113 |
ISSN: | 2330-4022 |
Title of parent work (English): | ACS Photonics |
Subtitle (English): | revealing absorption anticrossing by tuning the dielectric environment |
Publisher: | American Chemical Society |
Place of publishing: | Washington |
Publication type: | Article |
Language: | English |
Date of first publication: | 2017/07/19 |
Publication year: | 2017 |
Release date: | 2022/04/14 |
Tag: | absorption measurements; exciton plasmon coupling; hybrid nanoparticles; layer-by-layer deposition; strong coupling |
Volume: | 4 |
Number of pages: | 8 |
First page: | 1669 |
Last Page: | 1676 |
Funding institution: | DFG via graduate school SALSA |
DDC classification: | 5 Naturwissenschaften und Mathematik / 52 Astronomie / 520 Astronomie und zugeordnete Wissenschaften |
5 Naturwissenschaften und Mathematik / 53 Physik / 530 Physik | |
Peer review: | Referiert |
Publishing method: | Open Access / Green Open-Access |