Biomedical subjects

Axel Voigt

Publications and source records attributed to Axel Voigt.

2 recordsLinked to original sources

PubMed2005

Kinetic model for step flow growth of [100] steps.

A kinetic model for the step flow growth of [100] steps is derived. This model extends the implicit close-to-equilibrium assumption in the classical Burton-Cabrera-Frank theory to out-of-equilibrium growth regimes common in molecular beam epitaxy. In equilibrium, the kink density coincides with Burton, Cabrera, and Frank [Philos. Trans. R. Soc. London, Ser. A 243, 299 (1951)] but in a planar steady state solution for a periodic sequence of steps the kink density derivates and we analyze its scaling behavior with the step Peclet number. Furthermore, we observe a discontinuity of adatoms on the steps that might give a new explaination for step bunching.

Journal Article↗

PubMed2005

Complex shape evolution of electromigration-driven single-layer islands.

The shape evolution of two-dimensional islands through periphery diffusion biased by an electromigration force is studied numerically using a continuum approach. We show that the introduction of crystal anisotropy in the mobility of edge atoms induces a rich variety of migration modes, which include oscillatory and irregular behavior. A phase diagram in the plane of anisotropy strength and island size is constructed. The oscillatory motion can be understood in terms of stable facets that develop on one side of the island, and which the island then slides past. The facet orientations are determined analytically.

Journal Article↗