Localized-surface-plasmon enhanced luminescence from porous silicon by gold nanoparticles

The porous silicon (PS), decorated by Au nanoparticles (NPs) possessing strong localized-surface-plasmon (LSP) resonance, are prepared by conventional anodization method. Luminescence properties are studied systematically and an approximately ten-fold enhancement of photoluminescence has been observed with the decoration of Au NPs, which is mainly due to the resonance coupling between the LSP of Au NPs and the electronic excitation of PS. The other factors affecting the optical properties of the hybrid system, such as emission from Au NPs themselves and light multi-scattering, will be discussed and the underlying mechanisms will be analyzed. These results indicate that, despite many challenges, Au NPs can be potentially applied in the future silicon-based optoelectronics.