Volume 81, Number 2, January 2008
Article Number 26001
Number of page(s) 4
Section Condensed Matter: Structural, Mechanical and Thermal Properties
Published online 03 December 2007
EPL, 81 (2008) 26001
DOI: 10.1209/0295-5075/81/26001

Self-assembled Pt nanowires on Ge(001): Relaxation effects

U. Schwingenschlögl and C. Schuster

Institut für Physik, Universität Augsburg - 86135 Augsburg, Germany

received 19 September 2007; accepted in final form 7 November 2007; published January 2008
published online 3 December 2007

Absorption of Pt on the Ge(001) surface results in stable self-organized Pt nanowires, extending over some hundred nanometers. Based on band structure calculations within density functional theory and the generalized gradient approximation, the structural relaxation of the Ge$\hbox{--} $Pt surface is investigated. The surface reconstruction pattern obtained agrees well with findings from scanning tunneling microscopy. In particular, strong Pt$\hbox{--} $Pt dimerization is characteristical for the nanowires. The surface electronic structure is significantly perturbed due to Ge$\hbox{--} $Pt interaction, which induces remarkable shifts of Ge states towards the Fermi energy. As a consequence, the topmost Ge layers are subject to a metal-insulator transition.

68.43.Bc - Ab initio calculations of adsorbate structure and reactions.
73.20.-r - Electron states at surfaces and interfaces.
73.20.At - Surface states, band structure, electron density of states.

© EPLA 2008