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Simulation, Fabrication and Characterization of THz Metamaterial Absorbers
Published on: December 27, 2012
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Ultrasensitive Higher-Order Exceptional Points via Non-Hermitian Zero-Index Materials
Dongyang Yan1, Alexander S Shalin2,3, Yongxing Wang4
1Soochow University, School of Physical Science and Technology, Collaborative Innovation Center of Suzhou Nano Science and Technology, Jiangsu Key Laboratory of Frontier Material Physics and Devices, Suzhou 215006, China.
Physical Review Letters
|July 31, 2025
Summary
Researchers achieved higher-order exceptional points (EPs) in open optical systems. This breakthrough enables ultrasensitive sensing in purely lossy materials, advancing optical device capabilities.
Area of Science:
- Photonics and Optical Physics
- Non-Hermitian Physics
- Metamaterials
Background:
- Higher-order exceptional points (EPs) in coupled optical systems offer ultrasensitive responses.
- Fundamental physics of higher-order EPs in open scattering systems remain underexplored.
- Zero-index materials provide unique platforms for manipulating light waves.
Purpose of the Study:
- To explore and realize higher-order EPs in open scattering systems using non-Hermitian zero-index materials.
- To investigate the fundamental physics and characteristics of third-order EPs in a multi-channel setup.
- To demonstrate ultrasensitive responses in a purely lossy system near an absorbing EP.
Main Methods:
- Harnessing wave interference in non-Hermitian zero-index materials.
- Developing a three-channel model to investigate third-order EPs.
- Analyzing lasing, reflecting, and absorbing types of third-order EPs.
- Characterizing ultrasensitivity near the absorbing EP in a lossy system.
Main Results:
- Successfully realized higher-order EPs in an open scattering system.
- Identified three types of third-order EPs: lasing, reflecting, and absorbing.
- Demonstrated ultrasensitivity in a purely lossy system near a third-order absorbing EP.
- Showcased drastic output power changes in response to perturbations.
Conclusions:
- Higher-order EPs can be achieved in open scattering systems, expanding beyond coupled systems.
- The developed model provides a pathway to arbitrary-order EPs in open systems.
- These findings hold significant potential for the development of advanced optical sensing technologies.
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