Single and multiple pulse laser-induced breakdown in transparent dielectrics in the femto-nanosecond region

摘要

This review is devoted to a long-term investigation into the nature of the laser-induced damage of silicate glasses. As an important result, we show that the threshold power density of the intrinsic damage of the boro-silicate glass at ~1 μm wavelength does not depend on pulse duration from 2x10~(-13) to 3x10~(-8)s as long as self-focusing is avoided. This result cannot be explained by existing theories and indicates that the damage mechanism involves a collective response of a certain volume in the dielectric as a whole, rather than the accumulation of electrons via individual generation processes like multiphoton, tunneling, or avalanche. Special attention in the research was paid to investigation into the processes of multiple pulse damage and subthreshold modification of boro- and lead-silicate glasses.