Combining intense extreme ultraviolet and relativistic electron pulses for novel attosecond experiments.

Research Project, 2021 – 2025

Attosecond electron pulses are gaining recognition as a new and unique tool that can open up novel avenues of fundamental research and applications. Examples are electron microscopy with attosecond resolution, the generation of attosecond X-ray beams for investigating physical, chemical, and biological processes with unprecedented temporal resolution, or seeding of future free- electron lasers. Thus, detailed understanding of the generation mechanisms, increased control over their temporal properties, as well as fundamental understanding of their interaction with matter on attosecond timescales, are
of utmost importance.

In this project, we will combine intense attosecond extreme ultraviolet (XUV) laser pulses, generated through gas-phase high-order harmonic generation, with attosecond electron pulses, accelerated to relativistic velocities using laser
wakefield acceleration (LWFA), in experiments where the interaction between very strong, ultrafast, electric fields and matter will be explored on previously inaccessible timescales. The project includes several important developments and demonstrations. During the project we will: (1) develop and implement new techniques for the generation of isolated attosecond pulses of photons and electrons; (2) probe and optimize the ultrafast dynamics involved in LWFA using attosecond XUV pulses; and (3) measure the attosecond material response to the transient electric field of a relativistic attosecond electron pulse. The successful completion of the project will not only bring fundamental knowledge about the interaction of attosecond photon and electron pulses with matter, it will also provide essential technology for future studies and applications, in fields like ultrafast photonics, nanoscience and molecular electronics. In addition, the achieved knowledge will allow control of  the used electron acceleration mechanisms, with potential to produce tailored attosecond electron pulses for a wide variety of applications.