Photoinduced Ag-nanoparticle deposition on Fe-doped lithium niobate crystals

Abstract

We study the photoinduced deposition of Ag nanoparticles on Fe-doped LiNbO3 crystals by using an in situ probe. SEM and XPS analysis show that Ag metallic nanoparticles are close-packedly deposited on the crystal surface. Both 405 and 532nm laser are found effective for the photo-induced Ag deposition. The Ag deposition on the y-surface shows obvious anisotropy as compared to that on the + z-surface. Moreover, the Ag deposition on the + z-surface is found to start easily surrounding the focal point of the laser rather than at its center. Both photogalvanic and diffusion effects of photo-excited electrons are suggested to account for these features.