Interparticle interactions and time effects in very thin Fe-SiO2 granular films

Time decay and remanence measurements have been made on a series of very th in Fe-SiO2 granular thin films of varying composition. The susceptibility a nd the magnetic viscosity decreases drastically when the film thickness is thin enough to reach a two-dimensional arrangement of the granules. The mea sured values of the magnetic viscosity are very low (2% loss per decade) in the thinnest films so that further investigations in granular magnetic sys tems with higher anisotropy promise greater advantages for recording media. (C) 1999 American Institute of Physics. [S0021-8979(99)06511-1].