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Updated: May 14, 2026
10:28
Fabrication of Nanopillar-Based Split Ring Resonators for Displacement Current Mediated Resonances in Terahertz Metamaterials
Published on: March 23, 2017
Highly tunable nanoscale metal-insulator-metal split ring core ring resonators (SRCRRs)
Iman Zand1, Mohammad S Abrishamian, Pierre Berini
1Faculty of Electrical and Computer Engineering, KN Toosi University of Technology, Tehran 16314, Iran.
Optics Express
|February 8, 2013
Summary
A new nano-scale optical filter design using a split-ring core (SRC) offers tunable wavelength selectivity. Adjusting the SRC gap size and incorporating tunable materials enables precise control over resonant modes for optical switches and filters.
Area of Science:
- Photonics
- Nanotechnology
- Optical Engineering
Background:
- Metal-insulator-metal (MIM) square rings are used for optical filters.
- Existing designs have limitations in tunability and integration.
Purpose of the Study:
- To propose a novel nano-scale wavelength-selective optical filter.
- To demonstrate tunable resonant modes in the proposed structure.
- To develop a circuit model for predicting device performance.
Main Methods:
- Replacing the MIM square ring core with a split-ring core (SRC).
- Analyzing resonant modes supported by the SRC structure.
- Incorporating tunable materials within the SRC gap.
- Developing a transmission-line theory-based circuit model.
Main Results:
- The proposed resonator supports adjustable SRR-like resonant modes.
- Resonance tuning over hundreds of nanometers is achievable via SRC gap size.
- Varying refractive index (1-2) tunes modes by ~200-300 nm.
- Circuit model shows good agreement with numerical results.
Conclusions:
- The SRC resonator offers highly adjustable wavelength selectivity.
- The design is suitable for integrated nano-scale optical switches.
- The structure shows potential for advanced tunable optical filters.
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