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07:39
Determination of the Excitation and Coupling Rates Between Light Emitters and Surface Plasmon Polaritons
Published on: July 21, 2018
Fluorescence enhancement from individual plasmonic gap resonances.
Marcus Schmelzeisen1, Yi Zhao, Markus Klapper
1Max-Planck-Institute for Polymer Research, Ackermannweg 10-55128 Mainz, Germany.
ACS Nano
|May 21, 2010
Summary
Researchers observed a significant fluorescence enhancement in dye-loaded dendrimers positioned in nanoscale gaps between silver surfaces. This plasmonic effect amplified the dye
Area of Science:
- Plasmonics and Nanophotonics
- Fluorescence Spectroscopy
- Materials Science
Background:
- Dye-loaded polyphenylene dendrimers exhibit fluorescence.
- Plasmonic nanostructures can enhance light-matter interactions.
- Controlling nanoscale gaps is crucial for plasmonic effects.
Purpose of the Study:
- To investigate fluorescence enhancement of dye-loaded dendrimers in nanoscale gaps.
- To explore the role of sphere-on-plane plasmonic resonators.
- To understand the influence of gap geometry on optical properties.
Main Methods:
- Fabrication of a sphere-on-plane plasmonic resonator with a 2-3 nm gap.
- Utilizing dye-loaded polyphenylene dendrimers as the fluorescent source.
- Characterization using fluorescence spectroscopy and electron microscopy.
Main Results:
- Observed fluorescence enhancement of at least 1000 times compared to a flat surface.
- Identified hot luminescence and spectral shifts correlated with plasmonic resonance.
- Distinguished two classes of scattering resonators, with variations attributed to nanoscale gap morphology.
Conclusions:
- The sphere-on-plane geometry provides a controllable plasmonic resonator for significant fluorescence enhancement.
- Nanoscale variations in shape and roughness within the gap critically influence optical response.
- Observed spectral modifications indicate physical mechanisms beyond simple wavelength-dependent enhancement at small metal/dye separations.
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