Photoelectron holography constitutes a powerful tool for the ultrafast imaging of matter, as it combines high electron currents with subfemtosecond resolution, and gives information about transition amplitudes and phase shifts. Similarly to light holography, it uses the phase difference between the probe and the reference waves associated with qualitatively different ionization events for the reconstruction of the target and for ascertaining any changes that may occur. These are major advantages over other attosecond imaging techniques, which require elaborate interferometric schemes in order to extract phase differences. For that reason, ultrafast photoelectron holography has experienced a huge growth in activity, which has led to a vast, but fragmented landscape. The present review is an organizational effort towards unifying this landscape. This includes a historic account in which a connection with laser-induced electron diffraction (LIED) is established, a summary of the main holographic structures encountered and their underlying physical mechanisms, a broad discussion of the theoretical methods employed, and of the key challenges and future possibilities. We delve deeper in our own work, and place a strong emphasis on quantum interference, and on the residual Coulomb potential.

中文翻译：

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一切都与相位有关：超快全息光电子成像

光电子全息术构成了超快物质成像的强大工具，因为它将高电子电流与亚飞秒分辨率相结合，并提供有关跃迁幅度和相移的信息。与光全息术类似，它使用探针和参考波之间的相位差与性质不同的电离事件相关联，以重建目标并确定可能发生的任何变化。这些都是优于其他阿秒成像技术的主要优势，这些技术需要精心设计的干涉测量方案才能提取相位差。出于这个原因，超快光电子全息术的活动经历了巨大的增长，这导致了广阔但支离破碎的景观。本次审查是一项旨在统一这一格局的组织努力。这包括与激光诱导电子衍射 (LIED) 建立联系的历史记录、遇到的主要全息结构及其潜在物理机制的总结、对所采用理论方法的广泛讨论以及关键挑战和未来的可能性。我们深入研究自己的工作，并非常重视量子干涉和剩余库仑势。