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Updated: May 18, 2026
07:39
Determination of the Excitation and Coupling Rates Between Light Emitters and Surface Plasmon Polaritons
Published on: July 21, 2018
Plasmons and optical excitations in graphene rings
1Department of Applied Physics, Chalmers University of Technology, SE-412 96 Göteborg, Sweden. weihua.wang@chalmers.se
Journal of Physics. Condensed Matter : an Institute of Physics Journal
|September 14, 2012
Summary
This study investigates plasmon excitations in graphene ring structures using a semiclassical Drude model. Researchers found that symmetric plasmon modes decrease with increasing hole size, while antisymmetric modes show a more complex behavior.
Area of Science:
- Condensed Matter Physics
- Materials Science
- Nanophotonics
Background:
- Graphene exhibits unique electronic properties, including surface plasmon resonances.
- Understanding plasmon excitations in nanostructured graphene is crucial for optical applications.
Purpose of the Study:
- To investigate plasmon excitations in graphene ring structures.
- To analyze the influence of geometric parameters on plasmon mode energies.
- To explore optical excitation pathways for plasmon modes.
Main Methods:
- Utilizing a semiclassical Drude-like conductivity model for graphene.
- Employing a quasi-static self-consistent integral equation approach.
- Performing full-wave simulations with graphene optical conductivity from random phase approximation (RPA).
Main Results:
- Calculated all plasmon modes with different angular momentum (l).
- Identified dipole modes (l=1) coupling to radiation modes for optical excitation.
- Observed monotonic decrease in symmetric mode energies with increasing inner-to-outer radius ratio.
- Found non-monotonic behavior (decrease then increase) in antisymmetric mode energies.
Conclusions:
- Graphene ring geometry significantly affects plasmon mode energies.
- Symmetric and antisymmetric plasmon modes exhibit distinct dependencies on the hole-to-ring ratio.
- The study provides insights into optical excitation of graphene plasmons for potential device applications.
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