Biomedical subjects

den Nijs M

Publications and source records attributed to den Nijs M.

12 recordsLinked to original sources

PubMed2000

Anomalous roughness in dimer-type surface growth

We point out how geometric features affect the scaling properties of nonequilibrium dynamic processes, by a model for surface growth where particles can deposit and evaporate only in dimer form, but dissociate on the surface. Pinning valleys (hilltops) develop spontaneously and the surface facets for all growth (evaporation) biases. More intriguingly, the scaling properties of the rough one dimensional equilibrium surface are anomalous. Its width, W approximately Lalpha, diverges with system size L as alpha = 1 / 3 instead of the conventional universal value alpha = 1 / 2. This originates from a topological nonlocal evenness constraint on the surface configurations.

Journal Article↗

PubMed2000

Facet ridge end points in crystal shapes

We study equilibrium crystal shapes (ECS) near facet ridge end points (FRE) by means of a numerical study of a body-centered solid-on-solid model on a square lattice with an enhanced uniaxial interaction range. This tests the stability of the so-called stochastic FRE point where the model maps exactly onto one dimensional Kardar-Parisi-Zhang-type growth and where the local ECS is simple. We find that the generic shapes are more complex. They contain first-order faceted to rough boundaries terminating in Pokrovsky-Talapov-type end points, and first-order ridges inside the rounded part of the ECS where two rough surface orientations coexist.

Journal Article↗

PubMed1995