Extraordinary Hall effect and X-ray photoemission studies of two dimensional films of magnetic nanoclusters

The low energy cluster beam deposition technique (LECBD) is used to prepare nanostructured thin films from clusters (Co, Ag, and mixed Co–Ag) preformed in the gas phase. Two dimensional (2D)-films of isolated supported clusters randomly distributed on the substrate, as well as isolated clusters embedded in various matrices by a co-deposition technique are prepared. Magnetic properties of Co-clusters films with equivalent Co-thickness as low as 0.01 nm are investigated using the extraordinary hall effect (EHE) measurements. The results emphasize the very high sensitivity of the EHE-technique to study the magnetic behaviour of very thin cluster films. Complementary transmission electron microscopy observations and X-ray photoemission spectroscopy measurements (XPS) on mixed Co–Ag clusters are also performed to investigate on the cluster morphology (homogeneous CoAg-alloy or core-shell structure due to the surface segregation of Ag-atoms) which could influence the corresponding magnetic properties. # 2003 Elsevier B.V. All rights reserved.