Topological photonics is a rapidly emerging field of research in which geometrical and topological ideas are exploited to design and control the behavior of light. Drawing inspiration from the discovery of the quantum Hall effects and topological insulators in condensed matter, recent advances have shown how to engineer analogous effects also for photons, leading to remarkable phenomena such as the robust unidirectional propagation of light, which hold great promise for applications. Thanks to the flexibility and diversity of photonics systems, this field is also opening up new opportunities to realize exotic topological models and to probe and exploit topological effects in new ways. This article reviews experimental and theoretical developments in topological photonics across a wide range of experimental platforms, including photonic crystals, waveguides, metamaterials, cavities, optomechanics, silicon photonics, and circuit QED. A discussion of how changing the dimensionality and symmetries of photonics systems has allowed for the realization of different topological phases is offered, and progress in understanding the interplay of topology with non-Hermitian effects, such as dissipation, is reviewed. As an exciting perspective, topological photonics can be combined with optical nonlinearities, leading toward new collective phenomena and novel strongly correlated states of light, such as an analog of the fractional quantum Hall effect.

中文翻译：

---

拓扑光子学

拓扑光子学是一个快速发展的研究领域，其中几何和拓扑学思想被用来设计和控制光的行为。凝聚态量子霍尔效应和拓扑绝缘体的发现启发了人们的灵感，最近的进展表明，如何对光子也能设计类似的效应，从而导致了引人注目的现象，例如光的强大的单向传播，这为应用带来了广阔的前景。由于光子学系统的灵活性和多样性，该领域也为实现异乎寻常的拓扑模型以及以新的方式探究和利用拓扑效应开辟了新的机会。本文回顾了拓扑光子在各种实验平台上的实验和理论进展，包括光子晶体，波导，超材料，腔体，光力学，硅光子学和电路QED。讨论了如何改变光子系统的尺寸和对称性以实现不同的拓扑阶段，并讨论了理解拓扑与非厄米特效应（例如，耗散）之间相互作用的进展。作为令人兴奋的观点，拓扑光子可以与光学非线性相结合，从而导致新的集体现象和新颖的强相关光状态，例如分数量子霍尔效应的模拟。综述了了解拓扑与非厄米特效应（例如耗散）之间相互作用的进展。作为令人兴奋的观点，拓扑光子可以与光学非线性相结合，从而导致新的集体现象和新颖的强相关光状态，例如分数量子霍尔效应的模拟。综述了了解拓扑与非厄米特效应（例如耗散）之间相互作用的进展。作为令人兴奋的观点，拓扑光子可以与光学非线性相结合，从而导致新的集体现象和新颖的强相关光状态，例如分数量子霍尔效应的模拟。