Germanene on Al(111) grown at nearly room temperature

Abstract

A -R19.1° superstructure has been formed on Al(111) by Ge deposition at nearly room temperature, which is different from the previously reported germanene on Al(111) with 3×3 periodicity. By scanning tunneling microscopy, scanning tunneling spectroscopy, and density functional theory calculation, the atomic structure of this surface is predicted to be a periodic honeycomb lattice of Ge atoms formed on Al(111), in which one Ge atom per unit cell markedly protrudes into the vacuum side. The calculated band structure based on the predicted germanene/Al(111) structure indicates strong hybridization between the Ge layer and the Al(111) substrate.