Our institute is the only national institute that promotes a high-intensity, ultra-short laser pulse in Japan and actually one of the first institutions that utilizes a powerful Ti sapphire laser based research in the world. First, I briefly introduce our QST and KPSI and some recent activities on attosecond science, intense laser applications etc.
Then, I will talk about the laser-plasma accelerator development activities in KPSI.
When an intense, short-pulse laser, whose length is comparable to the plasma wavelength, is focused on underdense plasma, a plasma electron oscillation is excited behind the laser pulse. This plasma wave is called laser wake and its static electric field is called laser wakefield. The plasma density can determine the phase velocity of the wakefield, and it can trap and accelerate initially energetic electrons to high energy. This process is called laser-plasma acceleration, or laser wakefield acceleration (LWFA). LWFA is actively studied because it can provide compact, high-quality electron beams compared to conventional linear accelerators. We aim to realize a compact, X-ray free-electron laser (FEL) based on LWFA with the support of the JST MIRAI program (Creating new values that meet social and industrial needs by science and technology). As a milestone goal, we pursue to demonstrate lasing in a self-amplified spontaneous emission (SASE) regime in the extreme ultraviolet wavelength. Here, we show our recent electron beam parameters achieved in our laser electron platform LAPLACIAN in RIKEN SPring-8 Center and the latest experimental results.