空间自相位调制是一种三阶非线性光学效应，又称光学克尔效应。空间自相位调制的物理机制为激光诱导的非局域电子相干性，是一种集体激发行为，非线性光学响应，演生现象。物质中电子在光场的驱动下以光学频率运动，获得由外场决定的相位，分离区域之间保持固定的由光场决定的相位差，从而演生出非局域电子相干性，其衍射光的平行光分量在远场形成一系列同心嵌套的圆锥形发射，在远场屏上形成干涉环，此即空间自相位调制。基于激光诱导在量子材料中产生电子相干性，可以实现全光开关，具有“以弱光控制强光”的特性，功能类似于光子学中的“三极管”。本文简要综述空间自相位调制的物理机理研究及其在全光开关领域的应用前景，重点梳理空间自相位调制在新阶段的发展以及微观物理机制。

Spatial self-phase modulation (SSPM) is a third-order nonlinear optical response, also known as optical Kerr effect. The physics mechanism of SSPM is laser-induced nonlocal electron coherence, which is a collective excitation behavior, nonlinear optical response, and emergence phenomenon. Electrons in the matters move with optical frequency driven by light field and obtain phase determined by the external field. Electrons in separated domains preserve fixed phase difference and nonlocal coherence emerges. The parallel components of diffractive light form a group of concentric conical emissions, resulting in coherence rings in the far field screen. This phenomenon is SSPM. All-optical switching can be achieved based on laser-induced electron coherence in quantum materials, functioning as a “transistor” in photonics, because it can realize using a weak light to control a strong light. This article briefly reviews the investigations towards SSPM physics mechanism, as well as its potential applications in all-optical switching, emphasizing on the new progress and microscopic mechanism of SSPM.