Thermal roughening of an SOS-model with elastic interaction

TL;DR

This paper investigates how long-range elastic interactions between steps influence the thermal roughening transition of crystal surfaces using Monte Carlo simulations, revealing a significant increase in roughening temperature due to these interactions.

Contribution

It introduces a Monte Carlo simulation study of a solid-on-solid model with elastic dipole interactions, highlighting the impact of long-range forces on surface roughening.

Findings

Roughening temperature increases drastically with long-range interactions.

Anti-correlations between surface defects are enhanced by elastic interactions.

Multi-grid scheme effectively reduces computational effort for long-range potentials.

Abstract

We analyze the effects of a long-ranged step-step interaction on thermal roughening within the framework of a solid-on-solid model of a crystal surface by means of Monte Carlo simulation. A repulsive step-step interaction is modeled by elastic dipoles located on sites adjacent to the steps. In order to reduce the computational effort involved in calculating interaction energy based on long-ranged potentials, we employ a multi-grid scheme. As a result of the long-range character of the step interaction, the roughening temperature increases drastically compared to a system with short-range cutoff as a consequence of anti-correlations between surface defects.