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Microwave Photonics Systems Based on Whispering-gallery-mode Resonators
Published on: August 5, 2013
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Arbitrary order exceptional point induced by photonic spin-orbit interaction in coupled resonators
Shubo Wang1, Bo Hou2,3, Weixin Lu2
1Department of Physics, City University of Hong Kong, Hong Kong, China. shubwang@cityu.edu.hk.
Nature Communications
|February 21, 2019
Summary
Researchers demonstrate achieving arbitrary-order exceptional points in a simple waveguide-resonator system. This breakthrough enhances ultrasensitive detection of external perturbations, crucial for advanced sensing applications.
Area of Science:
- Quantum physics
- Photonics and optical engineering
- Condensed matter physics
Background:
- Non-Hermitian systems exhibit unique properties near exceptional points, where eigenvalues and eigenvectors coalesce.
- Higher-order exceptional points in optical structures can lead to extreme sensitivity to external perturbations.
Purpose of the Study:
- To demonstrate the achievement of arbitrary-order exceptional points in a simplified system.
- To investigate the potential for enhanced sensitivity to external perturbations using these exceptional points.
Main Methods:
- Utilizing a system of identical resonators placed near a waveguide.
- Exploiting unidirectional coupling between chiral dipolar states mediated by waveguide modes.
- Leveraging transverse spin-momentum locking for protection of the exceptional point.
Main Results:
- Successfully achieved arbitrary-order exceptional points in the waveguide-resonator system.
- Experimentally manifested various analytic response functions at the exceptional points in the microwave regime.
- Numerically and analytically demonstrated enhanced sensitivity to external perturbations near the exceptional point.
Conclusions:
- A simple waveguide-resonator system can realize arbitrary-order exceptional points.
- This system offers a robust platform for ultrasensitive detection and sensing applications.
- The findings pave the way for novel devices exploiting enhanced sensitivity at exceptional points.
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