基于文法的可重构集成光子光谱仪拓扑搜索
Grammar-based topology search for reconfigurable integrated photonic spectrometers
- Massachusetts Institute of Technology（麻省理工学院）
机构由 AI 辅助整理，请以论文原文为准。
AI总结：
该研究提出基于文法的拓扑优化框架，用于搜索可重构集成光子光谱仪的电路拓扑，确定核心设计规则，建立选择任务优化光子电路拓扑的系统途径。
AI中文摘要：
可重构集成光子光谱仪可通过少量开关元件生成指数级增长的测量态，是高性能便携式光谱仪的极具潜力的设计类别。然而，电路架构的选择在很大程度上仍依赖直觉驱动。我们提出一种基于文法的拓扑优化框架，该框架组合标准光子构建模块，对候选电路进行归一化和物理剪枝，并采用相干散射矩阵模型联合搜索拓扑与元件参数。设计通过与解码器无关的架构目标进行筛选，该目标结合了绝对奇异值噪声增益与多线条件数，从而兼顾响应多样性与光吞吐量。直接保留的光谱重建证实，该替代指标在高入射信噪比（SNR）下是重建质量的强预测因子。在研究的非谐振及谐振增强设计空间中，dFT及其变体提供了最佳的平衡性能；元件损耗增加时，更倾向于采用更浅的dFT变体，其中一个差分延迟级被模拟光相位器替代。无源与有源环未提供可归因于谐振幅度编码的稳健优势。结果确定了平衡互补干涉响应、高效终端收集及有限损耗电路深度为核心设计规则，并建立了在特定技术约束下选择任务优化光子电路拓扑的系统途径。
英文摘要：
Reconfigurable integrated photonic spectrometers can generate exponentially increasing measurement states from a small number of switching elements, making them a promising design class for high-performance portable spectroscopy. However, selecting a circuit architecture remains largely intuition driven. We introduce a grammar-based topology optimization framework that composes standard photonic building blocks, canonicalizes and physically prunes candidate circuits, and jointly searches topology and component parameters using a coherent scattering-matrix model. Designs are screened by a decoder-independent architecture objective that combines absolute singular-value noise gain with multi-line conditioning, thereby accounting for response diversity and optical throughput. Direct held-out spectrum reconstruction confirms that this surrogate is a strong predictor of reconstruction quality at high incident signal-to-noise ratio (SNR). Across the nonresonant and resonator-augmented design spaces examined, dFT and its variants offer the best balanced performance; increased component loss favors a shallower dFT variant in which one differential-delay stage is replaced by an analog optical phase shifter. Passive and active rings provide no robust advantage attributable to resonant amplitude coding. The results identify balanced complementary interferometric responses, efficient terminal collection, and limited lossy circuit depth as central design rules, and establish a systematic route for selecting task-optimized photonic circuit topologies under technology-specific constraints.
