Acceleration of electrons in THz driven structures for AXSIS

We describe initial steps in the development of the technology for a THz-driven accelerator that will drive a compact attosecond X-ray light source. THz-driven structures represent a promising emerging technology for compact acceleration of sub-femtosecond electron bunches. The millimeter scale of the driving field offers a favorable compromise between conventional accelerators which are proven and reliable but large and costly, and other advanced accelerators like plasma-based or laser-driven devices where the microscopic accelerator structures make device control difficult and limit the charge payload. By contrast the THz-driven structures are large enough to be fabricated by conventional means leading to a high degree of repeatability and control, can support field gradients that are significantly higher than in conventional accelerators, promising capabilities to produce sub-femtosecond electron bunches. In addition, the strong fields in THz based devices offer potential for compact, strong-field manipulation and diagnosis of electron bunches. Our results pave the way for development of a THz-based light source for sub-femtosecond investigation of material structure.