Applied Physics seminar: Dielectric laser accelerator – a vision toward chip-size accelerator and x-ray laser pointer


The size of a particle accelerator scales with the wavelength of the electromagnetic wave powering the accelerator structure. An optical-frequency accelerator built in dielectric is expected to be 100,000 times smaller than a conventional RF-frequency accelerator built in copper. Compared with copper, a dielectric has a much higher damage resistance to a laser field for high-gradient particle acceleration. Built upon lithographic technologies, a dielectric laser accelerator (DLA), operating at the optical frequencies with a pulse rate close to 1 GHz and an acceleration gradient up to 1 GV/m, is expected to generate high-energy attosecond electron bunches from a microchip with a moderate beam current. The bunched electrons are well suited for generating highly efficient electron superadiance in the EUV and x-ray spectrum. In this talk, I will first review and update the R&D of such accelerators in the past 20 years. I will then aggressively compare the peak and average brilliance of envisioned DLA-driven x-ray radiation sources against the 3rd– and 4th-generation synchrotron light sources. Since a DLA operates with a much smaller beam current, superior performance of a DLA-driven radiation source stands out when the brilliance under comparison is normalized to the beam power.