Pressure measurements and an analytical model for laser-generated shock waves in solids at low irradiance

Low amplitude shock waves (from 1 to 300 bar) have been generated in gold layers deposited on a quartz substrate, by laser pulses at an incident fluence from 0.4 to 4.0 J cm −2 . The quartz was used as a pressure gauge for recording the induced shock profile. At a fluence <1.4 J cm −2 , the shock pressure does not exceed 10 bar and the shock front is followed by a tension peak typical of an absorption in solid state. An analytical model of the compression–tension process has been developed, accounting for shock pressure and shock profile evolution as a function of irradiation conditions and material properties. From this model a mechanical interpretation is given to previous observations of spalling of the irradiated target surface.