Effect of adsorbed metal atoms on light absorption by a quartz surface

The optical properties of submonolayer metal films – silver, gold, indium – obtained by laser ablation on the surface of fused silica are studied. Extinction and absorption spectra of quartz, substrates with deposited films, as well as difference spectra are obtained. The minimum values of the effective thicknesses of metal films at which the nucleation of islands begins and localized plasmon resonances appear. It is shown that the absorption of the “quartz substrate-metal film” complex exceeds the sum of the absorptions by the quartz surface and by the metal atoms. The connection of this phenomenon with the transfer of charge from the metal to defects on the substrate surface is indicated.