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arXiv · 1204.2642

Evidence for Dirac Fermions in a honeycomb lattice based on silicon

Lan Chen·Cheng-Cheng Liu·Baojie Feng·Xiaoyue He·Peng Cheng·Zijing Ding·Sheng Meng·Yugui Yao·Kehui Wu
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Abstract

Silicene, a sheet of silicon atoms in a honeycomb lattice, was proposed to be a new Dirac-type electron system similar as graphene. We performed scanning tunneling microscopy and spectroscopy studies on the atomic and electronic properties of silicene on Ag(111). An unexpected $\sqrt{3}\times \sqrt{3}$ reconstruction was found, which is explained by an extra-buckling model. Pronounced quasi-particle interferences (QPI) patterns, originating from both the intervalley and intravalley scattering, were observed. From the QPI patterns we derived a linear energy-momentum dispersion and a large Fermi velocity, which prove the existence of Dirac Fermions in silicene.

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Lan Chen, Cheng-Cheng Liu, Baojie Feng, Xiaoyue He, Peng Cheng, Zijing Ding, Sheng Meng, Yugui Yao, Kehui Wu. 2012-04-12. Evidence for Dirac Fermions in a honeycomb lattice based on silicon. https://doi.org/10.1103/physrevlett.109.056804

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