Research of surface enhanced Raman scattering caused by surface plasmon of Ag nano-structures

Abstract

Silver nano-structures were synthesized through thermal evaporation. Scanning electron microscopy （SEM） observations showed that the silver nano-structures had several types of morphology. The optical properties of silver nano-structures were obtained by ultraviolet-visible spectrometry, which shows the resonance wavelength of surface plasmon. In this work, we demonstrate the surface enhanced Raman scattering （SERS） signals which allow us to track down the surface plasmon local field spectra of Ag nano-structures. To prove it, we also used rhodamine 6G deposited on samples. As a result, we show that the transmittance spectra and SERS enhancement gives a complete description of optical and electric field caused by surface plasmon resonance of Ag nano-structures. The difference of Raman enhancement also indicates that different structures give different surface plasmon intensity when combined with the result of SEM.