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XUV lasers are being exploited for radiography with high space, time and amplitude resolution of perturbations in laser driven targets. Information of importance for research into the possibility of generating energy by inertially confined fusion has been obtained using a saturated 15.4 nm neon-like Yttrium laser [1,2,3]. More recently further work has been carried out with a neon-like Ge laser also operating at saturation with prepulse drive on the J=0-1 transition at 19.6 nm. This has enabled new avenues to be explored including the effect on the laser driven targets of single mode perturbations in the drive intensity and the transient behavior of thermal smoothing of the perturbations as illustrated by figures 1 and 2. The change in XUV opacity of the dense shock compressed target material has also been studied and is of basic science interest as it gives the first direct measurement of the scaling with density of inverse Bremsstrahlung absorption in a strongly degenerate plasma [4].

We have constructed an ultra-fast time-dependant x-ray diffraction experiment in order to probe laser-induced phase transitions in solids. Such studies have previously been performed using laser probes in the infra-red, visible or ultraviolet spectral range. However, in order to directly probe structures in solids, it is necessary to use x-ray radiation. A laser system producing pulses with a duration of 100 fs has been set-up adjacent to a bending magnet at the Advanced Light Source (ALS). In addition an averaging streak camera with a temporal jitter smaller than 1.5 ps has been incorporated [1]. This diagnostic will permit us to study lattice disordering in materials such as Si. Single-shot measurements were also made using a Kentech streak camera.