Can one have preroughening of vicinal surfaces?

TL;DR

This paper explores the theoretical possibility of preroughening transitions in vicinal surfaces, proposing mechanisms like kink repulsions that could induce such phenomena, with potential relevance to observed anomalous roughening in specific materials.

Contribution

It demonstrates, within a terrace-step-kink model, that preroughening can occur due to specific short-range and extended-range step interactions.

Findings

Preroughening transition is theoretically possible in vicinal surfaces.

Short-range and extended-range step interactions can induce preroughening.

Relevance to anomalous roughening observed in Ag(115).

Abstract

We discuss the possibility that, besides roughening, a vicinal surface could display preroughening (PR), and consider the possible mechanisms for its promotion. Within the framework of a terrace-step-kink model, it turns out that a PR transition is possible, and could be induced by a short-range repulsion between parallel kinks along the same step or on adjacent steps, or even by some kind of extended range step-step repulsion. We discuss the possible relevance of this phenomenon to the anomalous roughening behaviour recently reported for Ag(115).