Study of the angular and polarization structures of radiation scattered by monolayers of metal-containing nanostructures during their oxidation

摘要

The angular and polarization scattering characteristics of copper, nickel, and palladium monolayers composed of quasi-monodisperse nanograins 2-5 nm in size, as well as aggregates and chains of these nanograins, have been investigated during oxidation of monolayers with different packing densities of particles in a monolayer. On the basis of the experimental data, a number of integral scattering characteristics of monolayers of different metals and the angular dependences of the scattering matrix elements for laser wavelengths in the visible range have been calculated and analyzed. It is demonstrated that the polarization properties of the angular structure and the scattering matrix elements depend strongly on the degree of order of the structures and the presence of chains in monolayers of metal-containing nanostructures. Oxidation of nanostructures leads to the chaotic distribution of metal cores in a nanostructure. It is shown that scattering from nanostructures is more sensitive to oxidation in comparison with absorption. A nonlinear concentration dependence of scattering intensity was observed for copper nanostructures on a quartz substrate near the plasma resonance (at 633 nm) of all structures under study and at 440 nm for nanostructures on a silicon substrate (i.e., at the wavelength corresponding to strong absorption in silicon).