English

DFT study of Pt-induced Ge(001) reconstructions

Materials Science 2013-11-15 v2 Computational Physics

Abstract

Pt deposited on a Ge(001) surface spontaneously forms nanowire arrays. These nanowires are thermodynamically stable and can be hundreds of atoms long. The nanowires only occur on a reconstructed Pt-Ge-surface where they fill the troughs between the dimer rows on the surface. This unique connection between the nanowires and the underlying substrate make a thorough understanding of the latter necessary for understanding the growth of the nanowires. In this paper we study possible surface reconstructions containing 0.25 and 0.5 of a monolayer of Pt. Comparison of calculated STM images to experimental STM images of the surface reconstruction reveal that the Pt atoms are located in the top layer, creating a structure with rows of alternating Pt-Ge and Ge-Ge dimers in a c(4x2) arrangement. Our results also show that Pt atoms in the second or third layer can not be responsible for the experimentally observed STM images.

Keywords

Cite

@article{arxiv.0901.2969,
  title  = {DFT study of Pt-induced Ge(001) reconstructions},
  author = {Danny E. P. Vanpoucke and Geert Brocks},
  journal= {arXiv preprint arXiv:0901.2969},
  year   = {2013}
}

Comments

16 pages, 13 figures