高平均功率光纤激光技术基础:模式

从具有不同模式特性的光纤激光研究现状出发，指出模式是光纤激光特性的核心参数之一。通过算例给出模式与光束质量之间的关系，引出模式分解技术是准确知晓模式组分和光束质量的关键，介绍常见的模式分解技术。针对模式不稳定效应这一限制光纤激光功率提升的新现象，归纳总结了不同因素对模式不稳定效应产生阈值的影响，梳理了提高阈值的物理原理和实现方法。从高阶模抑制、特定高阶模式和结构光场输出等三个方面介绍了光纤激光模式控制的最新进展。

Fundamentals of high-average-power fiber laser technology: Mode

Mode (transverse mode) is one of the key parameters, which could be deduced from the status of the fiber lasers with different mode properties. The relationship between mode and beam quality is analyzed by numerical calculations, based on which it is pointed out that mode decomposition is the key to well understand the mode constitution and beam quality, then the common mode decomposition techniques are introduced. Aimed at mode instability (MI), which is a new phenomenon that prohibits power scaling of fiber laser, various parameters affecting the threshold of MI are summarized, then the physical mechanism and technique to increase the threshold are concluded. The recent progress on mode control of fiber laser is introduced from the viewpoint of high-order-mode suppression and structured light field generation.