Optical properties of magnetic quasi-2D nanocomposites in the IR spectral region

The optical absorption spectra of magnetic quasi-2D Co island films and of hybrid Co/SiO2 multilayers in which island films are separated by SiO2 laye rs were studied. It was found that, when the Co film was masked by a thin S iO2 layer, the absorption considerably increased and exceeded 0.8. This was observed when the Co fraction was substantially lower than its critical va lue for the percolation transition. Moreover, the maximal absorption in thi s case weakly depends on both the effective film thickness and the number o f Co layers. Numerical analysis shows that the observed peculiarities of th e absorption spectra of the structures based on quasi-2D granulated Co film s are connected to a great extent with the peculiar features of the interfe rence effects occurring in such systems. (C) 2001 MAIK "Nauka/Interperiodic a".