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arXiv · 1112.1995

Diffusion Boundary Condition at Surface Steps

Xiaobin Niu·Hanchen Huang
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Abstract

This Communication reports a geometrical factor that is necessary in the diffusion boundary condition across surface steps. Specifically, this factor relates adatom concentration to its spatial gradient at a surface step, and it describes the fraction of jump attempts that cross the step. In this Communication, the authors show that the factor is 1/\Pi using theoretical formulation and further verify the formulation using numerical simulations for triangular, square, and hexagonal surface lattices.

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Xiaobin Niu, Hanchen Huang. 2011-12-09. Diffusion Boundary Condition at Surface Steps. https://doi.org/10.1016/j.jcrysgro.2012.04.015

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