Formation of laser-induced periodic surface structures (LIPSS) on tool steel by multiple picosecond laser pulses of different polarizationsGregorčič, Peter (Avtor) Sedlaček, Marko (Avtor) Podgornik, Bojan (Avtor) Reif, Jürgen (Avtor) LIPSSself-organization modellaser microprocessingLaser-induced periodic surface structures (LIPSS) are produced on cold work tool steel by irradiation with a low number of picosecond laser pulses. As expected, the ripples, with a period of about 90% of the laser wavelength, are oriented perpendicular to the laser polarization. Subsequent irradiation with the polarization rotated by 45° or 90° results in a corresponding rotation of the ripples. This is visible already with the first pulse and becomes almost complete - erasing the previous orientation - after as few as three pulses. The phenomenon is not only observed for single-spot irradiation but also for writing long coherent traces. The experimental results strongly defy the role of surface plasmon-polaritons as the predominant key to LIPSS formation.20162018-12-05 08:53:51Članek v reviji105545sl