Inhibited Al diffusion and growth roughening on Ga-coated Al (100)

Vincenzo Fiorentini; Donatella Fois; Sabrina Oppo

doi:10.1103/physrevlett.77.695

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Inhibited Al diffusion and growth roughening on Ga-coated Al (100)

Vincenzo Fiorentini·Donatella Fois·Sabrina Oppo

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Abstract

Ab initio calculations indicate that the ground state for Ga adsorption on Al (100) is on-surface with local unit coverage. On Ga-coated Al (100), the bridge diffusion barrier for Al is large, but the Al$\rightarrow$Ga {\it exchange barrier is zero}: the ensuing incorporation of randomly deposited Al's into the Ga overlayer realizes a percolation network, efficiently recoated by Ga atoms. Based on calculated energetics, we predict rough surface growth at all temperatures; modeling the growth by a random deposition model with partial relaxation, we find a power-law divergent roughness $w\sim t^{\,0.07\pm0.02}$.

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Vincenzo Fiorentini, Donatella Fois, Sabrina Oppo. 1996-07-04. Inhibited Al diffusion and growth roughening on Ga-coated Al (100). https://doi.org/10.1103/physrevlett.77.695

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