Abstract :
Temporal and spatial changes in the matrix of glasses (BK7 glass, fused silica, quartz) are investigated during and after
irradiation by pulsed laser radiation (100 f s < tp < 3 ps) at the wavelength l = 800 nm using high-speed photography, transient
absorption spectroscopy, and Nomarski-microscopy to visualize the changes of optical properties, plasma formation and
expansion, stress formation, modification, and cracking. Depending on the excitation conditions the glasses exhibit different
excitation and relaxation channels including various types of defect centers in the glass. Compared to laser irradiation with pulse
durations tp in the nanosecond regime, when the glasses are heated within the irradiation zone for many nanoseconds resulting in
an increase of the refractive index without cracking enabling the generation of photonic structures within the bulk, irradiation
with pulse durations in the picosecond regime leads to cracking, thus enabling marking in the bulk and at the surface
