Regensburg 2007 – scientific programme

Parts | Days | Selection | Search | Downloads | Help

MA: Fachverband Magnetismus

MA 2: Magnetic Particles/Clusters I

MA 2.6: Talk

Monday, March 26, 2007, 11:30–11:45, H10

Morphology and magnetism of compact surface-supported metal clusters — •Violetta Sessi, Jian Zhang, Jan Honolka, Axel Enders, and Klaus Kern — Max Planck Institute for Solid State Reaserch, Stuttgart, Germany

We study small, compact metal clusters fabricated by buffer layer assisted growth. With this method the clusters are formed by thermal evaporation onto the substrate surface which is covered by a noble gas buffer layer. The clusters are then brought into contact with the substrate by thermal desorption of the buffer layer. We will present a systematic STM and XMCD investigation of clusters formed under the same experimental conditions on different substrates, such as Cu(100), Ag(111) and Rh(111). We find that although the clusters form on the noble gas buffer layer, their final shape after making contact does depend on the substrates. The pronounced cluster mobility leads to cluster growth, bunching and step decoration on Cu or Ag substrates, but not on Rh. Moreover the islands are spherical on both Cu and Ag but flat on Rh. Diffusion and wetting of the substrate determine the final shape, size and clusters distribution upon contact with the surface. XMCD measurements are presented showing that also the magnetic properties of the clusters, such as anisotropy and blocking temperature, are determined by cluster-substrate interaction.