Interlayer Self-Diffusion on Stepped Pt(111)

Abstract

Challenging our understanding of epitaxy on clean and O-precovered Pt(111), the ab initio Schwoebel barrier calculated for downward self-diffusion across $A$-type steps on Pt(111) is only ${E}^{S}(A)\ensuremath{\approx}0.02\mathrm{eV}$. Geometric arguments explain why ${E}^{S}(B)$, the Schwoebel barrier at $B$-type steps, is more than an order of magnitude larger than ${E}^{S}(A)$.