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Distinguishing step relaxation mechanisms via pair correlation functions

D. B. Dougherty·I. Lyubinetsky·T. L. Einstein·E. D. Williams
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Abstract

Theoretical predictions of coupled step motion are tested by direct STM measurement of the fluctuations of near-neighbor pairs of steps on Si(111)-root3 x root3 R30 - Al at 970K. The average magnitude of the pair-correlation function is within one standard deviation of zero, consistent with uncorrelated near-neighbor step fluctuations. The time dependence of the pair-correlation function shows no statistically significant agreement with the predicted t^1/2 growth of pair correlations via rate-limiting atomic diffusion between adjacent steps. The physical considerations governing uncorrelated step fluctuations occurring via random attachment/detachment events at the step edge are discussed.

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D. B. Dougherty, I. Lyubinetsky, T. L. Einstein, E. D. Williams. 2004-08-20. Distinguishing step relaxation mechanisms via pair correlation functions. https://doi.org/10.1103/physrevb.70.235422

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