Rapid progress in photonics and nanotechnology brings many examples of resonant optical phenomena associated with the physics of Fano resonances, with applications in optical switching and sensing. For successful design of photonic devices, it is important to gain deep insight into different resonant phenomena and understand their connection. Here, we review a broad range of resonant electromagnetic effects by using two effective coupled oscillators, including the Fano resonance, electromagnetically induced transparency, Kerker and Borrmann effects, and parity–time symmetry breaking. We discuss how to introduce the Fano parameter for describing a transition between two seemingly different spectroscopic signatures associated with asymmetric Fano and symmetric Lorentzian shapes. We also review the recent results on Fano resonances in dielectric nanostructures and metasurfaces.

光子学和纳米技术的飞速发展带来了许多与Fano共振物理学相关的共振光学现象的例子，并在光学开关和传感领域得到了应用。为了成功设计光子器件，重要的是深入了解不同的共振现象并理解它们的连接。在这里，我们通过使用两个有效的耦合振荡器来回顾广泛的共振电磁效应，包括法诺共振，电磁感应的透明性，克尔克和波曼效应以及奇偶时间对称性破坏。我们讨论如何引入Fano参数来描述与不对称Fano和对称洛伦兹形状相关的两个看似不同的光谱特征之间的过渡。