Abstract The recent development of double photoemission (DPE) spectroscopy at surfaces using laser-based high-order harmonic generation in combination with time-of-flight electron spectroscopy is reviewed. Relevant experimental conditions including the solid angle for collecting photoelectron pairs, the energy and angular resolutions, as well as the repetition rate and the photon energy range of light sources are introduced. As examples, we provide an overview of laser-based DPE results on the noble metals Ag and Cu as well as transition metal oxides NiO and CoO. The DPE energy and angular distributions of photoelectron pairs are compared with emphasis on the possible indications of electron-electron interaction. Potential further developments including femtosecond time-resolved DPE experiments are outlined.

中文翻译：

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基于激光的表面双光发射光谱

摘要 综述了使用基于激光的高次谐波产生与飞行时间电子光谱相结合的表面双光发射 (DPE) 光谱的最新发展。介绍了收集光电子对的立体角、能量和角分辨率以及光源的重复率和光子能量范围等相关实验条件。例如，我们概述了贵金属 Ag 和 Cu 以及过渡金属氧化物 NiO 和 CoO 上基于激光的 DPE 结果。比较了光电子对的 DPE 能量和角度分布，重点是电子-电子相互作用的可能迹象。概述了包括飞秒时间分辨 DPE 实验在内的潜在进一步发展。