Key Laboratory for Laser Plasmas (Ministry of Education), School of Physics and Astronomy, Shanghai Jiao Tong University, Shanghai 200240, China.
Collaborative Innovation Center of IFSA (CICIFSA), Shanghai Jiao Tong University, Shanghai 200240, China.
Phys Rev Lett. 2018 Jan 26;120(4):044801. doi: 10.1103/PhysRevLett.120.044801.
Coulomb interaction between charged particles is a well-known phenomenon in many areas of research. In general, the Coulomb repulsion force broadens the pulse width of an electron bunch and limits the temporal resolution of many scientific facilities such as ultrafast electron diffraction and x-ray free-electron lasers. Here we demonstrate a scheme that actually makes use of the Coulomb force to compress a relativistic electron beam. Furthermore, we show that the Coulomb-driven bunch compression process does not introduce additional timing jitter, which is in sharp contrast to the conventional radio-frequency buncher technique. Our work not only leads to enhanced temporal resolution in electron-beam-based ultrafast instruments that may provide new opportunities in probing material systems far from equilibrium, but also opens a promising direction for advanced beam manipulation through self-field interactions.
在许多研究领域中，带电粒子之间的库仑相互作用是一种众所周知的现象。一般来说，库仑斥力会使电子束的脉冲宽度变宽，并限制许多科学设施的时间分辨率，如超快电子衍射和自由电子激光。在这里，我们展示了一种实际上利用库仑力来压缩相对论电子束的方案。此外，我们还表明，库仑驱动的束压缩过程不会引入额外的定时抖动，这与传统的射频聚束技术形成鲜明对比。我们的工作不仅提高了基于电子束的超快仪器的时间分辨率，这可能为探测远离平衡态的材料系统提供新的机会，而且还为通过自场相互作用进行先进的束流操控开辟了一个有前景的方向。
