Dynamic temporal pulse shaping in advanced ultrafast laser material processing

Phase-manipulated ultrafast laser pulses and temporally tailored pulse trains with THz repetition rates are promising new tools for quality micromachining of brittle dielectrics, allowing to adapt the laser energy delivery rate to the material properties for optimal processing. Different materials respond with specific reaction pathways to the sudden energy input depending on the efficiency of electron generation and on the ability to release the energy into the lattice. The sequential energy delivery with judiciously chosen pulse trains may induce softening of the material during the initial steps of excitation and change the energy coupling for the subsequent steps. We show that this can result in lower stress, cleaner structures, and allow for a material-dependent optimization process.