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Hierarchical Construction of Higher-Order Exceptional Points
Q Zhong1,2, J Kou3, Ş K Özdemir4
1Department of Physics, Michigan Technological University, Houghton, Michigan 49931, USA.
Physical Review Letters
|December 1, 2020
Summary
We present a new hierarchical method for creating higher-order exceptional points (HOEPs) in photonic systems. This approach simplifies HOEP realization and enhances resilience to fabrication imperfections.
Area of Science:
- Photonics
- Quantum Optics
- Materials Science
Background:
- Higher-order exceptional points (HOEPs) promise significant enhancements in light-matter interactions.
- Current methods for implementing HOEPs are complex and highly sensitive to fabrication errors.
Purpose of the Study:
- To develop a simplified and more robust approach for engineering photonic structures with HOEPs.
- To overcome the limitations of existing schemes in realizing HOEPs.
Main Methods:
- Introduced a hierarchical approach for designing photonic structures.
- Utilized parity-time symmetric optical microring resonators with chiral coupling.
- Employed full-wave simulations based on Maxwell's equations.
Main Results:
- Demonstrated a new, easier-to-build, and more resilient method for achieving HOEPs.
- Showed that uniform coupling is not necessary for HOEPs, indicating emergence from disorder.
- Confirmed results using realistic optical material simulations.
Conclusions:
- The hierarchical approach offers a practical pathway to realizing HOEPs.
- The discovered resilience to disorder and fabrication errors is a key advantage.
- This work paves the way for advanced photonic devices with enhanced light-matter interactions.
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