We have developed two models for the optical properties of heterogeneous media, based on the entropic analysis of their morphology. These models have been applied to actual granular metallic media close to the percolation. The models account well for the measured optical properties: the plasmon...

We studied resistivity, magnetoresistivity and magnetization in granular FeSiO2 films. In the hopping region, magnetoresistance was found to be as large as −5%, and is isotropic for different measurement geometry, which is the signature of giant magnetoresistance due to a spin-dependent...