Experimental Research on Saturated-Gain for Soft X-Ray Laser from Neon-Like Germanium Plasma

Amplification of spontaneous emissions at 19.6, 23.2 and 23.6nm have been observed by a “Multiple-Target Series Coupling” design in Ge plasma. The combined length for four targets is up to 56mm. The gain length product(GL) of small signal is up to 18 for both lines at 23.2 and 23.6nm, and the effective GL is 16.4 and 15.7 fox these two lines respectively. This two lines are obviously tending to saturation. The divergence of x-ray laser beam is about 4 mrad.