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arXiv · 0904.0297

Quasiperiodic free electron metal layers

A. K. Shukla·R. S. Dhaka·S. W. Dsouza·Sanjay Singh·D. Wu·T. A. Lograsso·M. Krajci·J. Hafner·K. Horn·S. R. Barman
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Abstract

Using electron diffraction, we show that free electron metals such as sodium and potassium form a highly regular quasiperiodic monolayer on the fivefold surface of icosahedral Al-Pd-Mn and that the quasiperiodicity propagates up to the second layer in sodium. Our photoelectron spectroscopy results show that the quasicrystalline alkali metal adlayer does not exhibit a pseudogap near the Fermi level, thought to be charactersitic for the electronic structure of quasicrystalline materials. Calculations based on density functional theory provide a model structure for the quasicrystalline alkali metal monolayer and confirm the absence of a pseudogap.

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A. K. Shukla, R. S. Dhaka, S. W. Dsouza, Sanjay Singh, D. Wu, T. A. Lograsso, M. Krajci, J. Hafner, K. Horn, S. R. Barman. 2009-04-02. Quasiperiodic free electron metal layers. https://arxiv.org/abs/0904.0297

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