1304.3308 (Baojie Feng et al.)

Observation of Dirac cone warping and chirality effects in silicene    [PDF]

Baojie Feng, Hui Li, Cheng-Cheng Liu, Tingna Shao, Peng Cheng, Yugui Yao, Sheng Meng, Lan Chen, Kehui Wu

We performed low temperature scanning tunneling microscopy (STM) and spectroscopy (STS) studies on the electronic properties of (r3xr3)R30{\deg} superstructure of silicene on Ag(111) surface. We found the existence of Dirac Fermion chirality through the observation of -3/2 power law decay of quasiparticle interference (QPI) patterns. Moreover, in contrast to the trigonal warping of Dirac cone in graphene, we found that the Dirac cone of silicene is hexagonally warped, which is confirmed by density functional calculations and explained by the unique superstructure of silicene. Our results indicate the (r3xr3)R30{\deg} superstructure can maintain the Dirac fermion characteristics, and is an ideal system to investigate the properties of silicene.

View original: http://arxiv.org/abs/1304.3308