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Design, Fabrication, and Experimental Characterization of Plasmonic Photoconductive Terahertz Emitters
Published on: July 8, 2013
Local capacitor model for plasmonic electric field enhancement
J H Kang1, D S Kim, Q-Han Park
1Department of Physics, Korea University, Seoul, 136-701, Korea.
Physical Review Letters
|April 28, 2009
Summary
We introduce a local capacitor model for accurately describing the lightning rod effect in nanoplasmonics. This model simplifies predicting electric fields near nanoscale metal edges, aiding optical nanocircuit design.
Area of Science:
- Nanoplasmonics
- Optical Nanocircuits
- Electromagnetism
Background:
- The lightning rod effect significantly enhances electric fields at nanoscale metal features.
- Accurate modeling of this effect is crucial for designing advanced nanoplasmonic devices.
Purpose of the Study:
- To develop a simple and quantitatively accurate model for the lightning rod effect in nanoplasmonics.
- To introduce and apply the concept of lambda-zone capacitance for predicting electric field enhancement.
Main Methods:
- A local capacitor model was developed.
- The model utilizes a proposed notion of lambda-zone capacitance.
- The model was applied to predict electric field enhancement near nanoscale metal edges (tips and gaps).
Main Results:
- The local capacitor model provides a simple yet accurate description of the lightning rod effect.
- Calculated enhancement factors show excellent agreement with rigorous theoretical results.
- The lambda-zone capacitance concept effectively predicts strong electric field induction.
Conclusions:
- The local capacitor model offers a powerful tool for nanoplasmonics research.
- Lambda-zone capacitance facilitates a blockwise treatment of nano-optical devices.
- This model serves as a fundamental element for building optical nanocircuits.
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