Application of a two-temperature model for the investigation of the periodic structure formation on Si surface in femtosecond laser interaction

Thibault J. Y. Derrien; Thierry Sarnet; Marc Sentis; Tatiana E. Itina

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arXiv · 1110.0368

Application of a two-temperature model for the investigation of the periodic structure formation on Si surface in femtosecond laser interaction

Thibault J. Y. Derrien·Thierry Sarnet·Marc Sentis·Tatiana E. Itina

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Abstract

We consider the case of surface irradiation by a small number of femtosecond laser shots leading to the formation of surface ripples. To explain this effect, we propose a numerical model that accounts for the following processes: (i) interference of the laser irradiation with an electromagnetic surface wave propagating on a silicon sample; (ii) free carrier formation and laser energy absorption; (iii) energy relaxation and electron-phonon coupling. We perform numerical calculations taking into account the interference of a surface wave with laser; and present the obtained simulation results in order to explain formation mechanisms of the experimentally observed patterns.

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Thibault J. Y. Derrien, Thierry Sarnet, Marc Sentis, Tatiana E. Itina. 2011-10-03. Application of a two-temperature model for the investigation of the periodic structure formation on Si surface in femtosecond laser interaction. https://arxiv.org/abs/1110.0368

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