Tuning of surface plasmon resonance by gold and silver bimetallic thin film and bimetallic dot array is investigated. Laser interference lithography is applied to fabricate the nanostructures. A bimetallic dot structure is obtained by a lift-off procedure after gold and silver thin film deposition by an electron beam evaporator. Surface plasmon behaviors of these films and nanostructures are studied using UV-Vis spectroscopy. It is observed that for gold thin film on quartz substrate, the optical spectral peak is blue shifted when a silver thin film is coated over it. Compared to the plasmon band in single metal gold dot array, the bimetallic nanodot array shows a similar blue shift in its spectral peak. These shifts are both attributed to the interaction between gold and silver atoms. Electromagnetic interaction between gold and silver nanostructures is discussed using a simplified spring model.

Surface enhanced resonance Raman and luminescence on plasmon active nanostructured cavities Appl. Phys. Lett. 97, 153110 (2010); 10.1063/1.3500836 Energy transfer from semiconductor nanocrystal monolayers to metal surfaces revealed by time-resolved photoluminescence spectroscopy Appl. Phys. Lett. 92, 133118 (2008); 10.1063/1.2906369 Self-assembled monolayer cleaning methods: Towards fabrication of clean high-temperature superconductor nanostructures Appl. Phys. Lett. 86, 154104 (2005); 10.1063/1.1899753Shape effects in plasmon resonance of individual colloidal silver nanoparticles Abstract. Colloidal lithography is applied to fabricate both large-area single metallic and bi-metallic layer nanostructures on quartz substrates for flexible tuning of surface plasmon resonance (SPR) effect. Au and Ag/Au metallic thin films are deposited over the self-assembled monolayer sphere masks, followed by the sphere mask removal to create periodic metallic nanostructures. The fabricated nanostructures are then characterized by UV-Vis spectroscopy and scanning electron microscopy to study their plasmonic effects. The influence of sphere size, metallic film thickness and composition of bi-metallic layers on plasmonic effects of these fabricated nanostructures was investigated. Tuning of the Au plasmon resonance peak by ~ 50 nm was recorded.