Analytic Formulas for the Orientation Dependence of Step Stiffness and Line Tension: Key Ingredients for Numerical Modeling

摘要

We present explicit analytic, twice-differentiable expressions for thetemperature-dependent anisotropic step line tension and step stiffness for thetwo principal surfaces of face-centered-cubic crystals, the square {001} andthe hexagonal {111}. These expressions improve on simple expressions that arevalid only for low temperatures and away from singular orientations. They arewell suited for implementation into numerical methods such as finite-elementsimulation of step evolution.