Monte Carlo Simulation of a Seeded Growth Model on a Triangular Lattice: Impact of Surface Impurities on the Final Morphology

Abstract

This study investigates the influence of surface contamination on the final morphology generated by a seed-mediated growth model on a two-dimensional triangular lattice. Using Monte Carlo simulations, we examine the interplay between growth rules (specifically rigid k-mer extension and flexible self-avoiding random walk (SARW) chains) and the geometric properties of pre-adsorbed impurities. Contrary to the initial hypothesis of a geometric matching between the growing species and the surface impurities, our results show that the final morphology in the jamming state is remarkably insensitive to the local symmetry or compactness of the impurities. For rigid k-mers, growth arrest is primarily driven by the impurity number density, which overrides any potential advantages of linear alignment with specific defect shapes. For SARW chains, the available void space and its topological connectivity limit the length, overshadowing the advantages of impurity compactness. Our findings reveal structural robustness in surface growth processes, where intrinsic growth rules dictate length scales, but the overall impurity coverage governs the overall feature distribution. This suggests that morphological outcomes are predictable based on total contamination levels, offering a simplified framework for controlling the growth of nanostructures in realistic, inhomogeneous environments.