Ultrafast nonlinear optical method for generation of planar shocks

Planar shocks generated by short pulse lasers are useful in studies of shoc k compression phenomena and may have applications in materials science, bio logy, and medicine. We have found the fluence profiles of 120-400 fs durati on Gaussian spatial mode incident laser pulses are reproducibly flattened v ia surface optical breakdown and Kerr focusing in thin dielectric substrate s at fluences just above the ablation threshold. These flat laser profiles have been used to produce planar shocks that are flat to 0.7 nm root-mean-s quare over a 75-100 mum diameter. (C) 2001 American Institute of Physics.