Swift heavy ion interaction with silver-silica nanocomposites: an experimental surface plasmon resonance study

In situ and ex situ surface plasmon resonance (SPR) studies on swift heavy ion (SHI) irradiated silver-silica nanocomposite (NC) films are reported. The size of the ion tracks under dense electronic excitation density induced by mega-electronvolt (MeV) and giga-electronvolt (GeV) ions irradiation is determined. The red shifting in the SPR peak position upon irradiation at incremented ion fluences is observed. The detailed analysis shows that SHI can be used to control the size and interactions among the nanoparticles. The origin of the change in the SPR peak shape is attributed to the strong fluctuations in sizes, rearrangement and partial deformation of nanoparticles by the process of melting, sputtering and reprecipitation in the tracks by invoking the thermal spike model.