基于矢量衍射理论并采用严格耦合波方法建立了一种新型的自溯源光栅正弦结构及入射条件与衍射效率的理论模型；通过控制变量法分析了自溯源光栅结构参数、激光入射条件对衍射效率的影响规律；搭建了光栅衍射效率测量系统；结合光栅方程，计算了不同Littrow角对应的衍射效率。仿真结果表明：入射波为TM偏振态、入射波长为420 nm、入射角为80°时，自溯源光栅−1级衍射效率处于峰值状态，为4.3%；在Littrow结构中，入射波为TM偏振态、入射波长为415.51 nm、Littrow角为77.5°时，自溯源光栅−1级衍射效率达到最大，且接近非Littrow角对应的自溯源光栅的峰值衍射效率。实验结果表明：入射波为TM偏振态、入射波长为405 nm、入射角从65°~85°改变时，自溯源光栅的衍射效率呈上升到平稳再下降的趋势，67°~80°改变时，其衍射效率达到平稳最大值，其结果为0.6%左右，其衍射效率变化趋势与理论计算结果一致。

高效、高质清洗是激光清洗的主要发展方向，也是实现激光清洗大规模工业应用的关键。国家重点研发计划“增材制造与激光制造”重点专项“大能量高重频脉冲激光智能清洗技术与装备”（共性关键技术类）针对航空和航天领域的装备制造和修护中，对精密、绿色、智能可控的新型清洗技术的迫切需求，解决多光束激光清洗多场耦合效应作用机制科学问题，突破大能量高重频纳秒激光器多维度增益协同调控、复杂曲面激光清洗残留物定位识别与路径规划和超宽幅面多光束联动拼接与能量控制等关键技术，开展大能量高重频纳秒脉冲激光器、激光高效高质清洗机制与关键技术和超宽幅面激光智能高效清洗成套工艺与装备研究。研究成果将在航天器表面热控涂层和飞机雷达罩表面除漆清洗去除中实现典型应用。

We report the modulation of epsilon-near-zero (ENZ) wavelength and enhanced third-order nonlinearity in indium tin oxide (ITO)/Au multilayer films. The samples consisting of five-layer 40 nm ITO films spaced by four-layer ultrathin Au films of different thickness, i.e., ITO(40 nm)/[Au(x)/ITO(40 nm)]₄, were prepared by magnetron sputtering at room temperature. The ENZ wavelength in the multilayer films is theoretically calculated and experimentally confirmed. The nonlinear refractive index and nonlinear absorption coefficient of the samples of x=0, 2, 3, 4 nm were determined using the Z-scan method at a wavelength of 1.064 µm. The large nonlinear refractive index n₂=1.12×10-13m2/W and nonlinear absorption coefficient β=-1.78×10-7m/W in the sample of x = 4 nm are both four times larger than those in the single-layer ITO film. The large optical nonlinearity due to the ENZ enhancement and carrier concentration is discussed. The results indicate that the ITO/Au multilayer films are promising for advanced all-optical devices.