Theoretical research on enhancement of gain for Ni-like Ag 13.9nm x-ray laser using a new two-layer target

For experiments such as on Ni-like Ag x-ray laser, driven by 1omega laser, the gain region is only several~nm depth near the targetsurface, this paper proposes a new two-layer target, in which a thinlayer (several nm depth) of silver is plated on the surface of someother materials. Furthermore, the Ni-like Ag 13.9~nm x-ray laserproduced by three new kinds of two-layer target with CH, Al and Ge asfoundation, was theoretically studied.