Theoretical study of spatiotemporal focusing for in-bulk laser structuring of dielectrics

For laser processing applications and creation of microstructures inside dielectric materials, focusing a femtosecond Gaussian pulse within the bulk these materials is commonly used. The energy mainly absorbed in focal spot due to nonlinear feature laser–dielectric interaction. Recently, get further control absorption, spatiotemporal technique, for which duration evolves course propagation, has been introduced. However, also leads an inclination wavefront, pulse-front tilt. In this work, influence tilt on propagation interaction studied by solving numerically Maxwell’s equations coupled induced electron dynamics dielectrics. qualitative behavior geometric features resulting absorption volume are presented. By varying intensity tilt, both aspect ratio symmetry changed. A simple model predicting evolution provided.