Direct observation of Dirac cone in multilayer silicene intercalation compound CaSi2

Eiichi Noguchi; Katsuaki Sugawara; Ritsuko Yaokawa; Taro Hitosugi; Hideyuki Nakano; Takashi Takahashi

doi:10.1002/adma.201403077

Direct observation of Dirac cone in multilayer silicene intercalation compound CaSi2

Adv Mater. 2015 Feb 4;27(5):856-60. doi: 10.1002/adma.201403077. Epub 2014 Dec 15.

Authors

Eiichi Noguchi¹, Katsuaki Sugawara, Ritsuko Yaokawa, Taro Hitosugi, Hideyuki Nakano, Takashi Takahashi

Affiliation

¹ Department of Physics, Tohoku University, Sendai, 980-8578, Japan.

PMID: 25502913
DOI: 10.1002/adma.201403077

Abstract

Calcium-intercalated multilayer silicene CaSi2 exhibits a massless Dirac-cone π-electron-band dispersion like graphene, while the Dirac point is about 2 eV away from the Fermi level due to diiimide-based charge transfer from the Ca atoms to the silicene layers. This indicates that the graphene-like electronic structure with a massless Dirac cone is stably formed in the metal-intercalated multilayer silicene.

Keywords: angle-resolved photoemission spectroscopy (ARPES); dirac cone; fermi surface; intercalation; silicene.