In many physical systems, the interaction with an open environment leads to energy dissipation and reduced coherence, making it challenging to control these systems effectively. In the context of wave phenomena, such lossy interactions can be specifically controlled to isolate the system, a condition known as a bound-state-in-continuum (BIC). Despite the recent advances in engineered BICs for photonic waveguiding, practical implementations are still largely polarization- and geometry-specific, and the underlying principles remain to be systematically explored. Here, we theoretically and experimentally study low-loss BIC photonic waveguiding within a two-layer heterogeneous electro-optically active integrated photonic platform. We show that coupling to the slab wave continuum can be selectively suppressed for guided modes with different polarizations and spatial structure. We demonstrate a low-loss same-polarization quasi-BIC guided mode enabling a high extinction Mach–Zehnder electro-optic amplitude modulator within a single Si3N4 ridge waveguide integrated with an extended LiNbO3 slab layer. By elucidating the broad BIC waveguiding principles and demonstrating them in an industry-relevant photonic configuration, this work may inspire innovative approaches to photonic applications such as switching and filtering. The broader impact of this work extends beyond photonics, influencing research in other wave dynamics disciplines, including microwave and acoustics.

中文翻译：

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多层电光有源光子集成电路平台中的连续束缚态引导模式


在许多物理系统中，与开放环境的相互作用会导致能量耗散和相干性降低，从而使有效控制这些系统变得具有挑战性。在波现象的背景下，可以专门控制这种有损相互作用来隔离系统，这种情况称为连续体束缚态（BIC）。尽管最近在用于光子波导的工程 BIC 方面取得了进展，但实际实现仍然主要是特定于偏振和几何形状的，并且基本原理仍有待系统地探索。在这里，我们从理论上和实验上研究了两层异构电光有源集成光子平台内的低损耗 BIC 光子波导。我们表明，对于具有不同偏振和空间结构的导模，可以选择性地抑制与板条波连续谱的耦合。我们展示了一种低损耗同偏振准 BIC 导模，可在单个 Si 内实现高消光马赫-曾德尔电光调幅器3氮4与扩展 LiNbO 集成的脊形波导3板层。通过阐明广泛的 BIC 波导原理并在行业相关的光子配置中进行演示，这项工作可能会激发开关和滤波等光子应用的创新方法。这项工作的更广泛影响超越了光子学，影响了其他波动力学学科的研究，包括微波和声学。