Comparative study of enhanced fluorescence from nano sculptured thin films Academic Article uri icon


  • When an electromagnetic wave interacts with a nano structured metallic surface or a nanoparticle, the electromagnetic fields near the surface are greatly enhanced by factors up to 1000. This phenomenon is due to two processes: (i) the 'lightning rod' effect, conventionally described as the crowding of the electric field lines at a sharp metallic tip and (ii) the excitation of localized surface plasmons at the metal surface. Both are responsible for the enhancement of fluorescence, second-harmonic generation and Raman scattering. For metal nanoparticles often both processes are involved in creating the localized enhanced near field. Since sculptured thin films (STFs) can have a rod like structure and an overall large porosity, it is expected that these structures will exhibit enhanced fluorescence and Raman signals. Results of comparative study of surface enhanced fluorescence are presented from STFs containing metal nano structures. The highest enhancement is found for Ag based STFs giving an enhancement factor of x14.

publication date

  • January 1, 2008