Component errors limit the scaling of multiport interferometers based on MZI meshes. These errors arise because imperfect MZIs cannot be perfectly programmed to the cross state. Here, we introduce two modified mesh architectures that overcome this limitation: (1) a 3-splitter MZI for generic errors, and (2) a broadband MZI+Crossing design for correlated errors. Because these designs allow for perfect realization of the cross state, the matrix fidelity no longer decreases with mesh size, allowing scaling to arbitrarily large meshes. The proposed architectures support progressive self-configuration, are more compact than previous MZI-doubling schemes, and do not require additional phase shifters. This eliminates a major obstacle to the development of very-large-scale linear photonic circuits.

中文翻译：

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无限可扩展的多端口干涉仪

组件误差限制了基于 MZI 网格的多端口干涉仪的缩放。这些错误的出现是因为不完美的 MZI 不能完美地编程到交叉状态。在这里，我们介绍了两种克服此限制的改进网格架构：(1) 用于通用错误的 3 分路器 MZI，以及 (2) 用于相关错误的宽带 MZI+Crossing 设计。因为这些设计允许完美地实现交叉状态，矩阵保真度不再随着网格大小而降低，允许缩放到任意大的网格。所提出的架构支持渐进式自配置，比以前的 MZI 倍增方案更紧凑，并且不需要额外的移相器。这消除了开发超大规模线性光子电路的主要障碍。