如何在低阈值小尺度(毫瓦或皮焦量级、微米以下)情况下激发非线性光学效应是近年来光学领域研究的重要课题。该研究最直接的应用需求就是光子集成芯片，这是未来实现超高速、大容量信息网络体系的基础。光子晶体具有类似于半导体能带的光子禁带(PBG)，被誉为“光子半导体”，为人们提供了一种新颖而又实用的操纵光子的物理手段，使低阈值、可集成非线性效应产生成为可能。越来越多的非线性效应在光子晶体中已经被发现，例如光子晶体慢光、带隙孤子、电磁感应透明、二次谐波产生、光学双稳态等，本文将着重对可用于光子集成器件开发的光子晶体非线性效应研究领域的一些主要成果和进展进行总结，介绍其相关应用并对光子晶体非线性效应研究作出展望。

How to excite the nonlinear optical effect in the case of low threshold (mW or pJ order) and small scale (μm or less) is a topic field of optical research in recent years. The most direct application requirement is photonic integrated circuit, which is the foundation to realize the ultra-high speed and large capacity information network in the future. Photonic crystals (PCs) have the photonic band gap (PBG) just like the semiconductor band for elec-tronics, so it is known as "photonic semiconductors". PCs provide a novel and practical means of manipulating photons, therefore the possibility of photonic integrated circuit with low threshold arises. More and more nonline-ar effects have been found in PCs, such as photonic crystal slow light, the band gap soliton, electromagnetic in-duction transparency, second harmonic generation and optical bistability. This paper will focus on the summaries of some major achievements and advances about PCs that would promote the nonlinear photonic integrated de-vices. Certainly the related applications will be introduced and the future outlook of the nonlinear PCs will be discussed.