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Dual-band unidirectional reflectionlessness at exceptional points in a plasmonic waveguide system based on near-field
Fei Zhao1, Tianyi Dai1, Cong Zhang1
1Department of Physics, College of Science, Yanbian University, Yanji, Jilin 133002, People's Republic of China.
Nanotechnology
|December 1, 2018
Summary
This study demonstrates dual-band unidirectional reflectionlessness in a plasmonic waveguide system. The novel design achieves near-zero reflection in one direction at two distinct frequencies, paving the way for advanced optical devices.
Area of Science:
- Optics and Photonics
- Plasmonics
- Non-Hermitian Physics
Background:
- Exceptional points (EPs) in non-Hermitian systems offer unique optical properties.
- Plasmonic waveguides enable subwavelength light confinement and manipulation.
- Unidirectional reflectionlessness is crucial for advanced optical components.
Purpose of the Study:
- To theoretically investigate dual-band unidirectional reflectionlessness at EPs.
- To explore a novel non-Hermitian plasmonic waveguide system.
- To achieve directional control of light with minimal reflection.
Main Methods:
- Theoretical analysis of a metal-insulator-metal waveguide coupled to two nanohole resonators.
- Investigation of near-field coupling effects.
- Calculation of reflection coefficients and quality factors at specific frequencies.
Main Results:
- Demonstrated dual-band unidirectional reflectionlessness at two distinct frequencies (205.20 THz and 194.56 THz).
- Achieved near-zero forward reflection at 205.20 THz and near-zero backward reflection at 194.56 THz.
- Obtained high quality factors (∼132 and ∼137) for unidirectional reflectionlessness.
Conclusions:
- The proposed system effectively achieves dual-band unidirectional reflectionlessness at exceptional points.
- This work provides a theoretical foundation for designing advanced plasmonic devices with directional light control.
- The findings have implications for integrated photonics and optical signal processing.
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