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Charge-density-wave formation by Van Hove nesting in the α-phase of Sn/Ge(111)

J. Gonzalez
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Abstract

We study the role of electron correlations in the formation of the surface charge-density-wave state in the Sn/Ge(111) interface. The Fermi energy of the overlayer is treated as a dynamical variable, which undergoes a substantial renormalization by the interaction. We show that the Fermi level turns out to be pinned to a Van Hove singularity in the density of states, which explains the formation of the charge-density-wave, the observation of a very flat band in photoemission experiments and the reduction of the spectral weight in the low-temperature phase.

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J. Gonzalez. 2000-04-04. Charge-density-wave formation by Van Hove nesting in the α-phase of Sn/Ge(111). https://doi.org/10.1103/physrevb.62.6928

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