Theoretical investigation on broadband THz deflectors for femtosecond electron beam diagnostics

Xiaoyu Liu, Micha Dehler, and Arya Fallahi, Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment 2020, Volume 986, 11 January 2021, 164722, online 12 October 2020; doi: 10.1016/j.nima.2020.164722

Streak cameras are commonly used to measure duration and temporal structure of sub-picosecond pulses. The resolution of a streak camera system strongly depends on the slew rate of the deflecting element, which approximately equals to the product of the amplitude and operation frequency of the device. As a combination of high frequency and high gradient, THz-driven deflector based streak camera system has been proposed as an attractive tool to reach femtosecond scale or even higher resolution. This study contributes to this growing area of research by investigating four promising designs of broadband THz deflectors with central frequencies at 0.3 THz. The basic properties of each structure, a systematical method to analyze their multipole fields and the derived fields are presented.

The scientific and technical impact of the study can be summarized as:

  • A detailed comparison between different technologies for developing THz streak cameras is presented
  • Nonlinear and high-order effects in streaking electron beams are investigated using THz devices
  • Best solutions in terms of available THz energy and electron beam properties for e-beam diagnostics are provided