The physics of a photonic structure is commonly described in terms of its apparent geometric dimensionality. On the other hand, with the concept of synthetic dimension, it is in fact possible to explore physics in a space with a dimensionality that is higher as compared to the apparent geometrical dimensionality of the structures. In this review, we discuss the basic concepts of synthetic dimension in photonics, and highlight the various approaches toward demonstrating such synthetic dimensions for fundamental physics and potential applications.

中文翻译：

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光子学中的合成尺度

通常根据其表观几何尺寸来描述光子结构的物理性质。另一方面，利用合成尺寸的概念，实际上有可能在具有比结构的表观几何尺寸更高的尺寸的空间中探索物理学。在这篇综述中，我们讨论了光子学中合成维数的基本概念，并着重介绍了为基本物理学和潜在应用展示这种合成维数的各种方法。