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Phase transition at finite temperature in one dimension: Adsorbate ordering in Ba/Si(111)3x2

Steven C. Erwin·C. Stephen Hellberg
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Abstract

We demonstrate that the Ba-induced Si(111)3x2 reconstruction is a physical realization of a one-dimensional antiferromagnetic Ising model with long-range Coulomb interactions. Monte Carlo simulations performed on a corresponding Coulomb-gas model, which we construct based on density-functional calculations, reveal an adsorbate-ordering phase transition at finite temperature. We show numerically that this unusual one-dimensional phase transition should be detectable by low-energy electron diffraction.

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Steven C. Erwin, C. Stephen Hellberg. 2005-04-18. Phase transition at finite temperature in one dimension: Adsorbate ordering in Ba/Si(111)3x2. https://doi.org/10.1016/j.susc.2005.04.026

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