Within the framework of this work an Embedding Atom Method (EAM) potential for the MnAs/Au interface system has been generated and successfully applied to investigate the main objective of the thesis: performing a Molecular Dynamics (MD) simulation of gold growth on MnAs and analyzing the grown gold structure. Further, this work provides a new effective potential, not only for MD simulations of MnAs/Au interface systems, but also for MnAs bulk systems. Both systems have never been described with MD simulations and, consequently, no effective potential had been developed for those systems until now.MnAs is a ferromagnetic transition metal compound, which can be grown as different shaped, sized, and arranged nanoclusters on GaAs substrates. It is therefore a promising material for magnetoelectronic devices. An example for such devices is non-volatile magnetic random-access memory (MRAM). MRAM functionality is based on the giant or tunnel magnetoresistance (GMR or TMR), already successfully used in read heads of magnetic hard drives. GMR-like behaviour has been observed when performing magnetotransport measurements through an arrangement of two MnAs nanocluster connected via a thin gold layer. For a theoretical treatment of those magnetotransport measurements, the preparing step is to analyze the structure of gold on MnAs. The analysis is done within a combined approach of MD and a force-matched potential for MnAs/Au.Force Matching - fitting a potential model to abinitio data - is an iterative optimization process with a various number of parameters. Since this process is by far no simple black box, detailed descriptions of the explicit steps and fitting strategies are given in this work.Validating the generated potential by comparison to structural properties and surface energies to abinitio and experimental values showed the reliability of the potential. With the potential, surface simulations were performed to analyze the stability of different surface facets and terminations for the deposition simulations. At two surfaces As dimers were forming and desorbing from the surface. In one case Mn diffusion into the substrate was observed.On the stablest surface, deposition simulations of gold on MnAs revealed a growth mode known as the Stranski-Krastanov growth. After building a wetting layer of one monolayer thickness, the deposited gold atoms grow mainly in an fcc structure with several stacking faults and twin boundaries. Further analysis showed that the lattice mismatch between gold and the MnAs surface is responsible for the defects. This mismatch also explains the orientation of the cubic fcc unit cells, which are tilted upright and stay on one corner with respect to the substrate.
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