Mechanical and electronic properties of MX/YTe (M = Ge, Sn; X = S, Se, Te) van der Waals heterostructures

In this work, we systematically investigated the mechanical and electronic properties of a group of van der Waals heterostructures (vdWHs) stacked by the MX (GeSe, GeTe, SnS and SnSe) and YTe monolayers based on the density functional theory. From the binding energies, the most stable geometry structures were determined: T-type GeSe/YTe, T-type GeTe/YTe, Y-type SnS/YTe and T-type SnSe/YTe. They exhibit excellent mechanical stability with anisotropic Young's moduli ranging from 71.81 N/m to 89.91 N/m. Meanwhile, the T-type GeSe/ YTe, GeTe/YTe and SnSe/YTe vdWHs show Ohmic contact, while the Y-type SnS/YTe vdWH shows the n-type Schottky contact with a barrier height of 0.395 eV. Furthermore, we also demonstrated that the transition of Y-type SnS/YTe from n-type Schottky contact to Ohmic contact can be realized by reducing the interlayer distance to 2.672 angstrom. The work is expected to provide valuable guidance for the fabrication and design of the next gen-eration of low-resistance nanodevices.

Automated summary

In this study, the mechanical and electronic properties of a group of van der Waals heterostructures (vdWHs) stacked by the MX (GeSe, GeTe, SnS, and SnSe) and YTe monolayers were systematically investigated through density functional theory. The most stable geometry structures were determined, and the vdWHs exhibited excellent mechanical stability with anisotropic Young's moduli. Additionally, different types of contact behavior were observed in the vdWHs, and the transition of one type of contact to another was demonstrated.