THz-driven Electron Bunch Compression and Timing Jitter Reduction for Relativistic Ultrafast Electron Diffraction Measurements

We discuss the results of a THz-driven electron bunch compression experiment in which interaction between a quasi-single-cycle THz pulse and a relativistic electron beam in a parallel plate waveguide produced a beam energy chirp for velocity bunching. Measurements at the SLAC MEV-UED facility show a simultaneous reduction in the bunch length and timing jitter by up to a factor of 3, improving the overall timing resolution for applications like ultrafast electron diffraction and other beam-based ultrafast measurements. This technique employs unique advantages of all-optical beam manipulation, including the inherent synchronization which allows the compensation of electron beam timing jitter and the high field gradient which enables efficient chirping of the electron beam in a sub-millimeter interaction region.