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arXiv · 1408.3188

Revealing the substrate origin of the linear dispersion of silicene/Ag(111)

M. X. Chen·M. Weinert
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Abstract

The band structure of the recently synthesized (3$\times$3) silicene monolayer on (4$\times$4) Ag(111) is investigated using density functional theory. A $k$-projection technique that includes the $k_\bot$-dependence of the surface bands is used to separate the contributions arising from the silicene and the substrate, allowing a consistent comparison between the calculations and the angle-resolved photoemission experiments. Our calculations not only reproduce the observed gap and linear dispersion across the K point of (1$\times$1) silicene, but also demonstrate that these originate from the $k_\bot$-dependence of Ag(111) substrate states (modified by interactions with the silicene) and \textit{not} from a Dirac state.

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M. X. Chen, M. Weinert. 2014-08-14. Revealing the substrate origin of the linear dispersion of silicene/Ag(111). https://doi.org/10.1021/nl502107v

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