Modifications in Near-Surface Layer of Transparent Dielectrics Ionized by Ultrashort Laser Pulses

Formation of spatially non-uniform mechanical tension in a transparent solid due to the lattice ionization under the intensive ultrashort laser pulses action is predicted and theoretically described. Within the framework of the continual theory of elasticity the estimation of both average values of deformation tensor and its variations in solid dielectric with non-uniform random distribution of ions was carried out. It was shown that three possible types of medium modification can arise in solid depending on its ionization degree and the thickness of ionized layer. Since the Coulomb fields inside ionized layer can be non-uniform, all three types of structuring can arise in solid simultaneously.