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Orientation Dependence of Step Stiffness: Failure of SOS and Ising Models to Describe Experimental Data

Sabine Dieluweit·Harald Ibach·Margret Giesen·T. L. Einstein
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Abstract

We have investigated the step stiffness on Cu(001) surfaces as a function of step orientation by two independent methods at several temperatures near 300 K. Both sets of data agree well and show a substantial dependence of the stiffness on the angle of orientation. With the exception of steps oriented along $<110>$, the experimental stiffness is significantly larger than the stiffness calculated within the solid-on-solid (SOS) model and the Ising-model, even if next nearest-neighbor interactions are taken into account. Our results have considerable consequences for the understanding and for the theoretical modeling of equilibrium and growth phenomena, such as step meandering instabilities.

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Sabine Dieluweit, Harald Ibach, Margret Giesen, T. L. Einstein. 2003-01-30. Orientation Dependence of Step Stiffness: Failure of SOS and Ising Models to Describe Experimental Data. https://doi.org/10.1103/physrevb.67.121410

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