Interaction of silicene and germanene with non-metallic substrates

3rd International Conference on Mathematical Modeling in Physical Sciences

物理学;数学

Houssa, M.^1 ; Scalise, E.^2 ; Van Den Broek, B.^1 ; Lu, A.^1,3 ; Pourtois, G.^3 ; Afanas'Ev, V.V.^1 ; Stesmans, A.^1

Department of Physics and Astronomy, University of Leuven, Leuven

B-3001, Belgium^1

Max Planck Institut für Eisenforschung, Dusseldorf

40237, Germany^2

Imec, 75 Kapeldreef, Leuven

B-3001, Belgium^3

关键词: Covalent bonding;    Dirac cones;    First-principles simulations;    Germanene;    Material layers;    Non-metallic substrates;    Out-of plane;    Van Der Waals interactions;   

Others  :  https://iopscience.iop.org/article/10.1088/1742-6596/574/1/012015/pdf
DOI  :  10.1088/1742-6596/574/1/012015

来源: IOP

【 摘 要 】

By using first-principles simulations, we investigate the interaction of silicene and germanene with various non-metallic substrates. We first consider weak van der Waals interactions between the 2D layers and dichalcogenide substrates, like MoX2 (X=S, Se, Te). The buckling of the silicene or germanene layer is correlated to the lattice mismatch between the 2D material and the MoX2 template. The electronic properties of silicene or germanene on these different templates then largely depend on the buckling of the 2D material layer: highly buckled silicene or germanene on MoS2 are predicted to be metallic, while low buckled silicene on MoTe2 is predicted to be semi-metallic, with preserved Dirac cones at the K points. We next study the covalent bonding of silicene and germanene on (0001) ZnS and ZnSe surfaces. On these substrates, silicene or germanene are found to be semiconducting. Remarkably, the nature and magnitude of their energy band gap can be controlled by an out-of-plane electric field.