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arXiv · 2510.20374

Elliptical-rod geometries enhance photonic band gaps in disordered stealthy hyperuniform photonic crystals

Kota Asakura·Kazuki Yamamoto·Akihisa Koga
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Abstract

We study two-dimensional photonic crystals composed of elliptical dielectric rods arranged according to stealthy hyperuniform point patterns. These patterns are characterized by the structure factor, which vanishes for 0 < |k| <= K, where k is the wave number and K denotes the cutoff wave number specifying the stealthiness of the pattern. The optical properties of the photonic crystals are analyzed by applying the plane-wave expansion method to Maxwell's equations. We demonstrate that photonic crystals composed of elliptical dielectric rods can exhibit larger photonic band gaps than those with cylindrical rods when both the rod orientation and aspect ratio are properly optimized. This behavior contrasts with that of periodic lattices such as triangular or square arrays. These findings shed light on the crucial role of structural anisotropy and aperiodic structure in enhancing photonic band-gap formation.

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Kota Asakura, Kazuki Yamamoto, Akihisa Koga. 2025-10-23. Elliptical-rod geometries enhance photonic band gaps in disordered stealthy hyperuniform photonic crystals. https://arxiv.org/abs/2510.20374

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