Structural and magnetic properties of PLD Co-Ag granular thin films

An investigation of static magnetic properties of CoxAg1-x (x = 0.25, 0.40) granular films grown by the pulsed laser deposition technique is reported for samples heat treated at different temperatures. Different terms have be en found to contribute to the observed temperature dependence of the magnet ization: isolated clusters, superparamagnetic particles and larger blocked particles. The increase of the deposition temperature up to 250 degrees C f or x = 0.40 leads to an increase of the fraction of superparamagnetic parti cles. An annealing treatment at 250 degrees C for x = 0.25 determines the g rowth of particles size. (C) 1999 Elsevier Science B.V. All rights reserved .