Optimization of Drive Pulse Configuration for a High-Gain Transient X-Ray Laser at 19.6nm

An Ne-like transient collisional excitation x-ray laser at 19.6 nm ( J = 0 → 1, 3p → 3s) was investigated numerically using a sophistic hydrodynamic code for a 100 μm thick Ge planar target irradiated by a nano-second prepulse followed by a picosecond main optical laser pulse. The simulations indicate that for a given peak intensity, the main pulse has an optimal duration to generate the maximum effective gain. An effective gain as high as 200 cm^-1 was obtained for the optimized drive pulse configuration.