Artificial Anisotropy Induced Bound States in the Continuum for Integrated Photonic Waveguide

Jinzhao Wang; Kunrun Lu; Yuanlin Li; Weiming Yao; Yang Feng; Yidi Cao; Wei Liu; Feng He; Jianan Duan; Yi Zou; Yongkang Dong; Xiaochuan Xu

arXiv · 2608.20992

Artificial Anisotropy Induced Bound States in the Continuum for Integrated Photonic Waveguide

Jinzhao Wang·Kunrun Lu·Yuanlin Li·Weiming Yao·Yang Feng·Yidi Cao·Wei Liu·Feng He·Jianan Duan·Yi Zou·Yongkang Dong·Xiaochuan Xu

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Abstract

Bound states in the continuum (BICs) enable counterintuitive light confinement without radiation loss, providing a powerful foundation for integrated photonic waveguides. However, existing BIC waveguides are predominantly realized through geometry-dependent designs, where the BIC condition is restricted to narrowly defined structural parameters, limiting design flexibility and practical applicability. Artificial optical anisotropy is introduced as a new design paradigm for BIC waveguides. Implemented using subwavelength-grating (SWG) metamaterials, continuously tailorable anisotropy provides an independent degree of freedom for deterministically reshaping the radiative continuum, enabling flexible formation and systematic control of BIC waveguides over a broad design space. Anisotropy-engineered symmetry breaking further enables controllable asymmetric radiation and precisely tailored field leakage. This paradigm transforms BIC waveguides from geometry-constrained structures into an anisotropy-engineered platform, establishing a general framework for programmable radiation engineering and next-generation integrated photonic devices.

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Jinzhao Wang, Kunrun Lu, Yuanlin Li, Weiming Yao, Yang Feng, Yidi Cao, Wei Liu, Feng He, Jianan Duan, Yi Zou, Yongkang Dong, Xiaochuan Xu. 2026-08-21. Artificial Anisotropy Induced Bound States in the Continuum for Integrated Photonic Waveguide. https://arxiv.org/abs/2608.20992

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