Mechanisms of Pulse to Pulse Pattern Evolution of Ultrafast Laser Induced Periodic Surface Structures Observed under Structured Illumination Microscopy

Summary form only given. The generation of Laser Induced Periodic Surface Structures (LIPSS) has attracted a worldwide attention due to the possibility to obtain micro and submicrometric structuring on various substrates with the flexibity of the laser irradiation tool. Many application fields are impacted by LIPSS, moslty related to adding functions to surfaces like wettability, optical properties and cellular differenciation [1-3]. When using ultrafast laser pulses for surface structuring, the low onset of thermal effects at low repetition rate enlarges the laser process parameters to observe LIPSS formation. Morover, various kinds of LIPSS are made distinguishable by finely tuning the irradiation conditions of the ultrafast pulses in terms of pulse energy, repetition rate, polarization and so on. We present here several experimental observations of LIPSS pulse to pulse pattern evolution mechanisms. ranging from a quasiconstancy of the pulse to pulse ripples pattern to significant variations of the periodic structures phase and orientation (see Fig. 1).