First-Principles Study of Atomic and Electronic Structure of Ba/Si(111)

Suklyun Hong, Hanchul Kim, Geunseop Lee, Ja-Yong Koo, Hongsuk Yi
2002 Journal of the Physical Society of Japan  
We report pseudopotential density-functional calculations of the "3 Â 1" phase of the Ba/Si (111) surface. To resolve the coverage issue of the Ba/Si(111) surface, we investigate various structural models with two Ba coverages: 1/3 ML and 1/6 ML. Based on the comparison of the simulated STM images for two coverages and the experimental images, it is found that the "3 Â 1" phase has 1/6 ML Ba and a 3 Â 2 structure with the honeycomb chain-channel Si reconstruction. The substrate reconstruction
more » ... quite similar to the Si(111)-3 Â 1 surface induced by 1/3 ML alkali-metals. The experimental semiconducting band gap is well reproduced by the LDA band structure.
doi:10.1143/jpsj.71.2761 fatcat:6akh35dyknchrd4s7s4h47mroy