DIELECTRIC PROPERTIES OF METALLOFULLERENE NANOSTRUCTURES

摘要

With the use of the Maxwell Garnett (MG) approximation and of the developed combined model of an effective medium (CMEM), we have investigated the spectral and concentration dependences of the real (n_(eff)) and imaginary (k_(eff)) parts of the complex effective refractive index of the Ag-C_(60) and Cu-C_(60) nanostructures in the visible range, as well as the dependence of their electrical conductivity in the near IR spectral region on the concentration of components. By comparing the results of theoretical calculations of the optical density with experimental data for the Ag-C_(60) and Cu-C_(60) composites produced by thermal vaporization and vacuum condensation it has been established that the CMEM has advantages over the MG approximation. The experimentally observed nonmonotonic spectral dependence of the optical density maxima of Cu-C_(60) composites coincides well with the CMEM-based calculations. Moreover, the application of this model made it possible to determine the percolation threshold in the near IR region for the nanostructures investigated.