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arXiv · 2003.04790

Mechanisms of surface nanostructuring of Al2O3 and MgO by grazing incidence irradiation with swift heavy ions

Marko Karlusic·Ruslan A. Rymzhanov·Jacques H. O'Connell·Lara Brockers·Kristina Tomic Luketic·Zdravko Siketic·Stjepko Fazinic·Pavo Dubcek·Milko Jaksic·Georgios Provatas·Nikita Medvedev·Alexander E. Volkov·Marika Schleberger
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Abstract

We experimentally discovered that Al2O3 and MgO exhibit well-pronounced nanometric modifications on the surfaces when irradiated under grazing incidence with 23 MeV I beam, in contrast to normal incidence irradiation with the same ion beam when no damage was found. Moreover, ions in these two materials produce notably different structures: grooves surrounded with nanohillocks on MgO surfaces vs. smoother, roll-like discontinuous structures on the surfaces of Al2O3. To explain these results, detailed numerical simulations were performed. We identified that a presence of the surface inhibits recrystallization process, thereby preventing transient tracks from recovery, and thus forming observable nanopatterns. Furthermore, a difference in the viscosities in molten states in Al2O3 vs. MgO explains the differences in the created nanostructures. Our results thus provide a deeper understanding of the fundamental processes of surface nanostructuring, potentially allowing for controlled production of periodic surface nanopatterns.

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Marko Karlusic, Ruslan A. Rymzhanov, Jacques H. O'Connell, Lara Brockers, Kristina Tomic Luketic, Zdravko Siketic, Stjepko Fazinic, Pavo Dubcek, Milko Jaksic, Georgios Provatas, Nikita Medvedev, Alexander E. Volkov, Marika Schleberger. 2020-03-10. Mechanisms of surface nanostructuring of Al2O3 and MgO by grazing incidence irradiation with swift heavy ions. https://arxiv.org/abs/2003.04790

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