Characteristics of compressional shocks resulting from picosecond heating of confined foils

Multikilobar shocks were generated in thin foils of copper using picosecond duration 1.054-μm laser pulses (1–10 J/cm2) to create plasmas in the region between the front surface and an overlying glass window. Michelson interferometry was used to optically probe the particle velocity history of the rear foil surface, from which the magnitude and temporal profile of the shock pressure were deduced. The pressure dependence on fluence was observed to be linear and the temporal profile of the wave has a rapid rise and a tail which followed a t−1/2 dependence, consistent with a simple model.