Germanene on MoS2 in PRL

The article ‘Structural and electronic properties of germanene on MoS2’ by Lijie Zhang, Pantelis Bampoulis and Qirong Yao has been accepted for publication in Physical Review Letters.

To date germanene has only been synthesized on metallic substrates. A metallic substrate is usually detrimental for the two-dimensional Dirac nature of germanene because the important electronic states near the Fermi level of germanene can hybridize with the electronic states of the metallic substrate. In this article the successful synthesis of germanene on molybdenum disulfide (MoS2), a band gap material is reported. Pre-existing defects in the MoS2 surface act as preferential nucleation sites for the germanene islands. The lattice constant of the germanene layer (3.8 ± 0.2 Å) is about 20% larger than the lattice constant of the MoS2 substrate (3.16 Å). Scanning tunneling spectroscopy measurements performed on the virtually continuous germanene layers reveal a V-shaped density of states, which is a clear hallmark of a two-dimensional Dirac material. These experimental results are in very good agreement with density functional theory calculations which have been performed by Dr. Rudenko and Prof. Katsnelson of the Radboud University in Nijmegen.