High temporal resolution THz streaking of high brightness relativistic electron beams

TL;DR

This paper systematically studies THz streaking structures for ultrafast characterization of relativistic electron beams, analyzing design, performance, and experimental validation.

Contribution

It introduces optimized horn-coupled waveguide geometries and provides a comprehensive analysis of their performance for ultrafast electron diagnostics.

Findings

Horn-coupled waveguides enhance streaking strength.

Experimental results validate the models across various parameters.

Design principles for THz streaking structures are established.

Abstract

We report a systematic experimental study of terahertz (THz) streaking structures for ultrafast characterization of relativistic, high-brightness electron beams. Horn-coupled waveguide geometries are investigated, enabling a comparative characterization of streaking strength, dispersion, transmission, and temporal fidelity. Analytical models and electromagnetic simulations are used to describe the dependence of streaking power on the waveguide dimensions and the drive frequency. Experimentally, the structures are characterized using compressed electron beam from an RF photoinjector over a range of THz field strengths, beam energies, and bunch durations. These results establish general design principles and performance limits for THz streaking structures applicable to ultrafast electron beam diagnostics.