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arXiv · 1204.3743

Coarsening scenarios in unstable crystal growth

Sofia Biagi·Chaouqi Misbah·Paolo Politi
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Abstract

Crystal surfaces may undergo thermodynamical as well kinetic, out-of-equilibrium instabilities. We consider the case of mound and pyramid formation, a common phenomenon in crystal growth and a long-standing problem in the field of pattern formation and coarsening dynamics. We are finally able to attack the problem analytically and get rigorous results. Three dynamical scenarios are possible: perpetual coarsening, interrupted coarsening, and no coarsening. In the perpetual coarsening scenario, mound size increases in time as L=t^n, where the coasening exponent is n=1/3 when faceting occurs, otherwise n=1/4.

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Sofia Biagi, Chaouqi Misbah, Paolo Politi. 2012-07-03. Coarsening scenarios in unstable crystal growth. https://doi.org/10.1103/physrevlett.109.096101

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