Surface plasmon enhanced photoluminescence from porous silicon nanowires decorated with gold nanoparticles

We demonstrate similar to 8-fold photoluminescence enhancement in porous Si nanowires via coupling of the surface plasmon of Au nanoparticles. We find that the formation of an insulating SiOx layer during the Au nanoparticle growth is essential to the photoluminescence enhancement. A schematic energy-level diagram is proposed to interpret the experimental results.