来自单预群聚电子束的自太赫兹与X射线自由电子激光同步
Self-Synchronized Terahertz and X-Ray Free-Electron Lasers from a Single Pre-Bunched Electron Beam
AI总结：
该研究提出从单预群聚电子束产生本征同步的强场窄带太赫兹与X射线自由电子激光的方案，解决了现有装置的系统复杂度高、时间抖动等问题，为两类泵浦-探测实验提供了可靠平台。
AI中文摘要：
结合强太赫兹（THz）与X射线脉冲的超快泵浦-探测光谱，是研究材料复杂结构与电子动力学的关键工具。然而，当前结合太赫兹源与X射线自由电子激光（FEL）的装置常存在系统复杂度高、固有时间抖动或太赫兹脉冲特性受限的问题。本文实验展示了从单预群聚电子束产生本征同步、强场、窄带太赫兹与X射线自由电子激光的方案。让电子束依次通过X射线与太赫兹放大器，呈现出高度协同的过程：初始的周期性太赫兹密度调制显著提升了X射线自由电子激光脉冲能量，同时在强X射线发射中稳定留存，驱动产生高功率、窄带太赫兹辐射。由于二者源自同一电子束团，两种脉冲本征保持精确恒定的时间延迟。这种无抖动方案构建了高度可靠的平台，适用于X射线泵浦/太赫兹探测及太赫兹泵浦/X射线探测实验。
英文摘要：
Ultrafast pump-probe spectroscopy combining intense terahertz (THz) and X-ray pulses is a critical tool for investigating complex structural and electronic dynamics in materials. However, current setups combining THz sources and X-ray free-electron lasers (FELs) often suffer from high system complexity, inherent timing jitter, or limited THz pulse properties. Here, we experimentally demonstrate the generation of intrinsically synchronized, strong-field, narrow-band THz and X-ray FELs from a single pre-bunched electron beam. Sequentially passing the beam through X-ray and THz amplifiers reveals a highly synergistic process: the initial periodic THz density modulation notably boosts the X-ray FEL pulse energy, while robustly surviving the intense X-ray emission to drive high-power, narrow-band THz radiation. Originating from the same electron bunch, the two pulses inherently maintain a precise, constant time delay. This jitter-free scheme establishes a highly reliable platform tailored for both X-ray-pump/THz-probe and THz-pump/X-ray-probe experiments.
