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Updated: Jul 18, 2025
10:28
Fabrication of Nanopillar-Based Split Ring Resonators for Displacement Current Mediated Resonances in Terahertz Metamaterials
Published on: March 23, 2017
7.8K
Near-Field Spectroscopy of Individual Asymmetric Split-Ring Terahertz Resonators
Yuezhen Lu1, Lucy L Hale2, Abdullah M Zaman1
1School of Engineering, New Engineering Building, Lancaster University, Gillow Ave, Bailrigg, Lancaster LA1 4YW, U.K.
ACS Photonics
|August 21, 2023
Summary
This study introduces a new terahertz aperture scanning near-field microscope (a-SNOM) technique for detailed analysis of individual metamaterial resonators. The method enables precise mapping of confined and weakly radiative modes, advancing terahertz photonics research.
Area of Science:
- Terahertz (THz) photonics and metamaterials
- Near-field microscopy and spectroscopy
- Subwavelength optics and optoelectronics
Background:
- Metamaterial resonators are crucial for terahertz (THz) devices like modulators and detectors.
- Characterizing THz metamaterial modes is challenging, relying on indirect array measurements.
- Understanding individual resonator modes is key for advanced THz applications.
Purpose of the Study:
- To develop and demonstrate a broadband time-domain spectroscopic method for individual metamaterial resonators.
- To enable direct mapping and quantitative analysis of confined and weakly radiative modes.
- To overcome limitations of far-field characterization techniques for subwavelength structures.
Main Methods:
- Utilized a THz aperture scanning near-field microscope (a-SNOM) for broadband time-domain spectroscopy.
- Employed a cross-polarized configuration within the a-SNOM setup.
- Investigated individual metamaterial resonators to probe supported modes.
Main Results:
- Successfully mapped strongly confined modes supported by individual metamaterial resonators.
- Enabled quantitative analysis of these confined modes using time-domain a-SNOM.
- Demonstrated the capability to investigate weakly radiative modes via the cross-polarized configuration.
Conclusions:
- The presented time-domain a-SNOM technique offers direct and quantitative characterization of metamaterial resonator modes.
- This method overcomes the challenges of indirect far-field measurements.
- The findings significantly advance the development of metamaterial-based optoelectronic platforms for THz photonics and fundamental research.
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