The modification of transparent materials is enabled by focused ultrashort laser pulses. Single pass processing up to several millimeters can be achieved by the usage of elongated beam profiles. We studied the mechanical separability in dependence of the material thickness. As simulations show, asymmetric beam profiles can cause modifications with preferential direction reducing the necessary breaking force. Pump-probe microscopy is implemented to examine the laser-matter-interaction. We present a measured 3D-reconstruction of the transient interaction inside the material and elucidate the desired crack formation. We demonstrate beam shaping concepts to create a new, efficient and robust class of Bessel-like beams, which can be used to achieve a preferred crack direction. We verify the concept by modification and separation of silicate glasses.

The industrial maturity of ultrashort pulsed lasers has triggered the development of a plethora of material processing strategies. Recently, the combination of these remarkable temporal pulse properties with advanced structured light concepts has led to breakthroughs in the development of laser application methods, which will now gradually reach industrial environments. We review the efficient generation of customized focus distributions from the near-infrared down to the deep ultraviolet, e.g., based on nondiffracting beams and threedimensional-beam splitters, and demonstrate their impact for micro-and nanomachining of a wide range of materials. In the beam shaping concepts presented, special attention was paid to suitability for both high energies and high powers.

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