Three-step model of the laser-induced periodic surface structures (LIPSS) formation on metal surfaces Текст научной статьи по специальности «Физика»

LP-I-14

Three-step model of the laser-induced periodic surface structures (LIPSS) formation on metal surfaces

E. Gurevich1, S. Maragkaki2, Y. Levy3, T. Derrien3, N. M. Bulgakova3

1Ruhr-University Bochum, Applied Laser Technologies, Bochum, Germany

2IESL-FORTH, Ultrafast Laser Micro andNano Processing, Heraklion, Greece

3HiLASE Centre, Institute of Physics of the Czech Academy of Sciences, Dolni Brezany, Czech

Republic

Although laser-induced periodic surface structures (LIPSS) are studied for more than 50 years, the physical background of the periodic pattern formation is still under discussion. Here we consider femtosecond single-pulse ablation of metals. Each laser pulse modifies the sample surface in three consequent steps: (1) the incident light energy heats the electrons; (2) the hot electrons heat the lattice; (3) liquid melt appears and resolidifies on the sample surface. In frames of the suggested model, the observed period of the LIPSS is influenced by all these three processes [1,2,3]. Here we report our experimental results of the on LIPSS upon laser ablation of copper in different liquids [4] and test the influence of the liquid environment on the hydrodymanic instabilities, which can develop in the melt. The theoretical results are compared with the experimental findings.

References

[1] E. L. Gurevich, Mechanisms of femtosecond LIPSS formation induced by periodic surface temperature modulation. Applied Surface Science 374, 56-60 (2016).

[2] E. L. Gurevich, Y Levy, SV Gurevich, N. M. Bulgakova, Role of the temperature dynamics in formation of nanopatterns upon single femtosecond laser pulses on gold.Physical Review B 95, 054305 (2017).

[3] S. Maragkaki, T. J.Y. Derrien, Y. Levy, N. M. Bulgakova, A. Ostendorf, E. L. Gurevich, Wavelength dependence of picosecond laser-induced periodic surface structures on copper. Applied Surface Science 417, 88-92 (2017).

[4] S. Maragkaki, A. Elkalash, E. L. Gurevich, Orientation of ripples induced by ultrafast laser pulses on copper in different liquids. Applied Physics A 123, 721 (2017).