Multi-millijoule, deeply saturated X-ray laser at 21 nm and its early applications at PALS

We present a brief overview of the development of soft X-ray lasers (XRL), recently carried out at the PALS (Prague Asterix Laser System) Research Centre. The PALS a is newly established laboratory and its hardware relating to X-ray lasers was introduced in the 2nd Symposium on Advanced Photon Research at JAERI in November 2000. The main achievement of the first X-ray laser experimental campaign at PALS is deeply saturated soft X-ray laser at 21.2 nm operating in double-pass regime. It uses as the active medium a 30-mm zinc plasma column produced by net energy of ∼500 J. A multilayer mirror mounted in a compact and fully automated pad makes it possible to carry out ∼100 X-ray shots. The laser provides a narrowly collimated and highly coherent beam with energy of about 4mJ, corresponding to peak power of ∼40MW, and represents one of the most powerful soft X-ray lasers demonstrated to date. (author)