Faceted-Rough surface between thermodynamically rough and atomically rough surfaces

This work assessed surface roughness based on calculations of a squared surface (or interface) width, W 2, employing a Monte Carlo technique in conjunction with a near-equilibrium steady state. This value is associated with the surface height–height correlation function. These calculations used a restricted solid-on-solid (p-RSOS) model together with step–step attractions stemming from quantum mechanics. Prolonged Monte Carlo calculations performed at sufficiently low temperatures near equilibrium demonstrated that the surface had a “faceted rough” structure that was thermodynamically rough. The roughness exponent was α=0.602 for a system size of L>ld and a time interval t>td, where ld is the mean distance between two-dimensional nuclei situated at a faceted microstep edge and td is the mean time for a monatomic step to detach from a faceted macrostep. However, the same surface was atomically and thermodynamically smooth for L