Self-Organization on Unstable Vicinal Surfaces with Competing Interactions

TL;DR

This paper investigates how long-range attractions and short-range repulsions between steps on vicinal crystal surfaces lead to self-organized patterns, with a focus on the influence of interaction ranges on surface stability and pattern scaling.

Contribution

It demonstrates that the scaling exponent depends solely on the range of long-range attractions, revealing a new understanding of surface pattern formation and stability.

Findings

Scaling exponent depends only on attraction range

Shorter-ranged attractions do not destabilize surfaces

Numerical analysis confirms theoretical predictions

Abstract

Long-ranged step-step attractions destabilize the vicinal crystal surfaces. Their competition with shorter-ranged step-step repulsions results in self-organized patterns. The exponent in the time-scaling of their characteristic size is influenced only by the range of the attractions but not by the range of the repulsions as we show based on precise numerical analysis of two different minimal models. Another anisotropy we identify is that the vicinal surface is not destabilized by shorter-ranged attractions.