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Non-Hermitian Stealthy Hyperuniformity
Gitae Lee1, Seungmok Youn1, Ikbeom Lee1
1Intelligent Wave Systems Laboratory, Department of Electrical and Computer Engineering, Seoul National University, Seoul, 08826, South Korea.
Advanced Science (Weinheim, Baden-Wurttemberg, Germany)
|August 6, 2026
Summary
We introduce non-Hermitian hyperuniformity and stealthiness to describe wave physics in open systems with correlated disorder. This extends parity-time (PT) symmetry concepts, revealing new scattering phases and dynamics in materials science.
Area of Science:
- Condensed Matter Physics
- Wave Physics in Open Systems
- Materials Science
Background:
- Parity-time (PT) symmetry has expanded crystalline phases to gain-loss media.
- Engineering disorder for wave manipulation is a growing area of interest.
- Non-Hermitian frameworks are needed to study correlated disorder.
Purpose of the Study:
- To generalize hyperuniformity and stealthiness to non-Hermitian systems with correlated disorder.
- To extend the scattering-microstructure correspondence to open systems.
- To explore new wave phenomena in non-Hermitian materials.
Main Methods:
- Formulation of non-Hermitian hyperuniformity and stealthiness.
- Extension of statistical crystallography to non-Hermitian materials.
- Analysis of microstructural statistics and scattering properties.
Main Results:
- Non-Hermitian hyperuniformity and stealthiness encompass Hermitian counterparts.
- Real-imaginary cross-correlations are irrelevant for hyperuniformity but essential for stealthiness.
- Unidirectional scattering phases, inaccessible in Hermitian systems, are revealed.
- Unique band coalescence and stochastic exceptional-point dynamics observed in the strong scattering regime.
Conclusions:
- Non-Hermitian hyperuniformity and stealthiness provide a framework for correlated disorder in open systems.
- This work connects non-Hermitian wave physics with materials science descriptors.
- New scattering phases and dynamics are accessible in engineered non-Hermitian materials.
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