Formation of Cu–Pt nanocontacts in STM breaking junction simulations: MD simulations and one-dimensional diffusion model

Abstract

In this paper, we propose a new theoretical approach that combines classical MD method and a one-dimensional diffusion model. We have shown that our approach allows to extrapolate the results of MD simulations to the experimental timescale. As an example, the formation of Cu–Pt nanocontacts in the STM-BJ experiments was investigated. STM-BJ simulations with copper STM tips and Cu–Pt surface alloys were performed in a wide range of temperatures (300–900 K), number of Pt atoms in the substrate (1–7) and for different orientations ((100), (110) and (111)) of the STM tip. Using our approach, we predicted that it is possible to use the STM-BJ technique to prepare Cu–Pt nanocontacts. The presented approach should work well in all cases when the diffusion of atoms occurs via interlayer jumps.