Mounding in Epitaxial Surface Growth

TL;DR

This paper provides a comprehensive analysis of the Villain-Lai-Das Sarma equation, revealing that mound-forming terms naturally emerge under renormalization, enhancing understanding of surface growth phenomena like mounding.

Contribution

It demonstrates that mound-forming terms are generated by the Villain-Lai-Das Sarma equation under renormalization, clarifying the theoretical basis of surface mounding.

Findings

Mound-forming terms are generated under renormalization.

Widely studied Langevin equations are special limits of the full theory.

The analysis advances understanding of surface growth phenomena.

Abstract

For the past two decades the Villain-Lai-Das Sarma equation has served as the theoretical framework for conserved surface growth processes, such as molecular-beam epitaxy. However some phenomena, such as mounding, are yet to be fully understood. In the following, we present a systematic analysis of the full, original Villain-Lai-Das Sarma equation showing that mound forming terms, which should have been included initially on symmetry grounds, are generated under renormalisation. A number of widely studied Langevin equations are recovered as limits or trivial fixed points of the full theory.