标题： 从原子到台阶：晶体演化的微观起源 显示英文标题

标题： From atoms to steps: The microscopic origins of crystal evolution

摘要： BCF晶体生长理论在描述表面物理中的广泛现象方面取得了成功。 典型的晶体表面相对于一个晶面略有偏离；因此，BCF理论将这些系统视为由分隔台阶的台面组成的阶梯状结构。 吸附原子（adatoms）以连续密度表示，在台面上扩散，台阶通过吸收或释放这些adatoms而移动。 在这里，我们通过从一个原子尺度的、动力学受限的固-固沉积（KRSOS）模型中推导出一个简单的一维（1D）理论版本，来揭示BCF理论的微观起源，而无需外部材料沉积。 我们在KRSOS模型中将时间依赖的adatom密度和台阶位置定义为适当的系综平均值，从而揭示了BCF理论的非平衡统计力学起源。 我们的分析表明，BCF理论在低adatom密度区域是有效的，这与理想气体近似适用于稀薄气体的方式非常相似。 我们找到了表面保持在低密度区域的条件，并讨论了对BCF模型修正的微观起源。 显示英文摘要

摘要： The BCF theory of crystal growth has been successful in describing a wide range of phenomena in surface physics. Typical crystal surfaces are slightly misoriented with respect to a facet plane; thus, the BCF theory views such systems as composed of staircase-like structures of steps separating terraces. Adsorbed atoms (adatoms), which are represented by a continuous density, diffuse on terraces, and steps move by absorbing or emitting these adatoms. Here we shed light on the microscopic origins of the BCF theory by deriving a simple, one-dimensional (1D) version of the theory from an atomistic, kinetic restricted solid-on- solid (KRSOS) model without external material deposition. We define the time-dependent adatom density and step position as appropriate ensemble averages in the KRSOS model, thereby exposing the non-equilibrium statistical mechanics origins of the BCF theory. Our analysis reveals that the BCF theory is valid in a low adatom-density regime, much in the same way that an ideal gas approximation applies to dilute gasses. We find conditions under which the surface remains in a low-density regime and discuss the microscopic origin of corrections to the BCF model.