화학공학소재연구정보센터
Applied Surface Science, Vol.387, 698-706, 2016
Formation of laser-induced periodic surface structures (LIPSS) on tool steel by multiple picosecond laser pulses of different polarizations
Laser-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. (C) 2016 Elsevier B.V. All rights reserved.