Mass-filtered ferromagnetic alloy clusters on surfaces

Mass filtered FeCo clusters with diameters in the order of magnitude of 12 nm were prepared in a new developed, continuously working cluster source and deposited on a Si surface. The AFM measurements exhibit a height being smaller than the diameter for free particles which can be explained by particle-support interaction. Larger clusters are due to the mass selecting process in an electrostatic quadrupole which separates with different m/e ratios. Magnetic properties were determined by X-ray magnetic circular dichroism (XMCD) with elemental specification. (C) 2004 Elsevier B.V. All rights reserved.