超快有序选择性电子成像与光谱学
Ultrafast order-selective electron imaging and spectroscopy
AI总结：
该研究综述了飞秒光电子动量显微镜与超快透射电子显微镜等技术进展，利用超快有序选择性电子成像与光谱学，为研究量子材料等的非平衡动力学提供了高时空分辨的新途径。
AI中文摘要：
能量与动量领域的超快泵浦-探测光谱学已成为探测量子材料非平衡动力学的不可或缺工具，揭示了超快能量转换与光诱导相变的路径。不同模态可独特地访问支撑这些材料功能的耦合晶格、电荷与自旋自由度。然而，研究技术相关的纳米级器件还需高空间分辨率。尽管电子显微镜可提供纳米级成像，但它常缺乏此类研究所需的同步超快时间分辨率与光谱特异性。在此视角下，我们综述了暗场电子显微镜与光电子显微镜的最新进展，聚焦两种互补技术：飞秒光电子动量显微镜与超快透射电子显微镜。它们的应用可全面洞察电子、晶格与自旋子系统的超快动力学。这些有序选择性电子成像与光谱学技术为微观理解量子材料、纳米结构及器件中的非平衡现象开辟了广泛的科学机遇。
英文摘要：
Ultrafast pump-probe spectroscopies in energy and momentum have become indispensable for probing non-equilibrium dynamics in quantum materials, revealing pathways in ultrafast energy conversion and light-induced phase transitions. Different modalities uniquely access the coupled lattice, charge, and spin degrees of freedom that underpin the functionality of these materials. However, investigating technologically relevant nanoscale devices also requires high spatial resolution. Although electron microscopy provides nanometer-scale imaging, it frequently lacks the simultaneous ultrafast temporal resolution and spectroscopic specificity needed for such studies. In this perspective, we review recent advances in dark-field electron and photoelectron microscopy, focusing on two complementary techniques: femtosecond photoelectron momentum microscopy and ultrafast transmission electron microscopy. Their application enables comprehensive insights into the ultrafast dynamics of the electron, lattice, and spin subsystems. These order-selective electron imaging and spectroscopy techniques open broad scientific opportunities for a microscopic understanding of non-equilibrium phenomena in quantum materials, nanostructures and devices.
