The "multilayer silicene" films were grown on Ag(111), with increasing thickness above 30 monolayers (ML). We found that the "multilayer silicene" is indeed a bulk Si(111) film. Such Si film on Ag(111) always exhibits a root(3)xroot(3) honeycomb superstructure on surface. Delocalized surface state as well as linear energy-momentum dispersion was revealed by quasiparticle interference patterns (QPI) on the surface, which proves the existence of Dirac fermions state. Our results indicate that bulk silicon with diamond structure can also host Dirac fermions, which makes the system even more attractive for further applications compared with monolayer silicene.
@article{arxiv.1405.7534,
title = {Persistent Dirac Fermion State on Bulk-like Si(111) Surface},
author = {Jian Chen and Wenbin Li and Baojie Feng and Peng Cheng and Jinglan Qiu and Lan Chen and Kehui Wu},
journal= {arXiv preprint arXiv:1405.7534},
year = {2014}
}