Chen, Lan; Cheng-Cheng, Liu; Feng, Baojie; He, Xiaoyue; Cheng, Peng; Ding, Zijing; Meng, Sheng; Yao, Yugui; Wu, Kehui
arXiv.org,
04/2012
Paper, Journal Article
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.
