Ab initio study of the electronic structure of Co adatom on Cu(111) surface

We present the ab initio Density Functional study of the electronic structure of Co adatoms on Cu (111) surface. A number of Scanning Tunneling Spectroscopy (STS) experiments performed on the systems which contain magnetic adatoms on the noble metal surfaces (e.g., Co, Ce on Cu, Ag, Au (111) planes) [1, 6, 7] report the observation of intriguing resonances at the Fermi energy. However, the interpretation of these experiments in terms of the Kondo physics is not totally conclusive and gave rise to many questions that are still to be answered. The first step towards understanding the meaning of these experiments is to understand the electronic structure of such systems. The so called supercell approximation is used to simulate a Cu slab consisting of Cu (111) planes. The electronic properties of Co adatom on Cu (111) surface is studied in a symmetric 2 x 2 supercell in the xy directions with fifteen Cu (111) and two Co planes in the z direction. It is observed that Co is in the d⁸ high spin state with the magnetic moment of 1.7 μB per Co atom. The width of Co d DOS is a result of the coupling with the Cu sp surface and bulk states. At least the first three Cu layers of the bulk Cu slab have significant influence on the electronic properties of Co.Science, Faculty ofPhysics and Astronomy, Department ofGraduat