Theoretical approach to point defects in a single transition metal dichalcogenide monolayer: conductance and force calculations in MoS$_{{2}}$

Abstract

We present here a small review on our exhaustive theoretical study of point defects in a MoS$_{{2}}$ monolayer. Using Density Functional Theory (DFT), we characterize structurally and electronically different kinds of defects based on S and Mo vacancies, as well as their antisites. In combination with a Keldysh–Green formalism, we model the corresponding Scanning Tunneling Microscopy (STM) images. Also, we determine the forces to be compared with Atomic Force Microscopy (AFM) measurements, and explore the possibilities of molecular adsorption. Our method, as a support to experimental measurements allows to clearly discriminate the different types of defects. Finally, we present very recent results on lateral conductance calculations of defective MoS$_{{2}}$ nanoribbons. All these findings pave the way to novel applications in nanoelectronics or gas sensors, and show the need to further explore these new systems.

Keywords

• Electronic structure
• Defects
• MoS$_{{2}}$
• DFT
• STM/AFM
• Molecular adsorption