Ultrashort Pulse Laser Processing Of Silica At High Repetition Rates - From Network Change To Residual Strain

This paper reports on the analysis of silica-based glasses after processing with ultra-short laser pulses at high repetition rates. Heat accumulation leads to strong local heating of the glass. The subsequent quenching results in fictive temperature rise that scales with the repetition rate. Consequently, the relative volume change leads to residual tensile strain within the modified volume of larger than 10-3, which is confirmed by wide-angle X-ray scattering (WAXS) measurements. Studying the surface topography after cleaving of laser-modified regions allows for quantification of the corresponding elastic strain as well as the glass density behaviour on the fictive temperature.