Gain measurements of the Cthinsp;VI 3dndash;2ptransition (18.2 nm) from the wallhyphen;confined carbon plasmas produced by a CO2laser

摘要

We propose a 1hyphen;cmhyphen;long cylinderhyphen;type target as the gain medium of a recombinationhyphen;pumped extremehyphen;ultraviolet (XUV) laser. The gain medium plasma was pumped by a longhyphen;pulse CO2laser (400 J energy in 50 ns pulse duration). At the Cthinsp;VI 3dndash;2ptransition (18.2 nm) we obtained the gainhyphen;length product up to 2.4, which was estimated from the line intensity ratio of the axial to transverse directions. The electron temperature of 54 eV and density of 1.2times;1019cmminus;3near the cylinder wall measured using softhyphen;xhyphen;ray spectroscopy satisfied the condition for the generation of the population inversion betweenn=3 and 2 levels of the Cthinsp;VI ions.