Segmented Terahertz Electron Accelerator and Manipulator (STEAM)

We present a segmented THz based device (STEAM) capable of performing multiple high-field operations on the 6D-phase-space of ultrashort electron bunches. With this single device, using only a few microjoules of single-cycle THz radiation, we have shown record THz-based acceleration of more than 30 keV, with a peak acceleration field gradient of around 70 MV/m. At the same time, the STEAM device can also manipulate the electrons that show high focusing gradient (2 kT/m), compression of electron bunches down to 100 fs and streaking gradient of 140 urad/fs, which offers temporal profile characterizations with resolution below 10 fs. The STEAM device can be fabricated with regular mechanical machining tools and supports real-time switching between different modes of operation. It paves the way for the development of THz-based compact electron guns, accelerators, ultrafast electron diffractometers and Free-Electron Lasers.