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.
@article{arxiv.0904.0297,
title = {Quasiperiodic free electron metal layers},
author = {A. K. Shukla and R. S. Dhaka and S. W. Dsouza and Sanjay Singh and D. Wu and T. A. Lograsso and M. Krajci and J. Hafner and K. Horn and S. R. Barman},
journal= {arXiv preprint arXiv:0904.0297},
year = {2009}
}