Light emission from silicon/gold nanoparticle systems

Photoluminescent nanostructured semiconductor/metal systems consisting of silicon nanocrystals and gold nanoparticles are obtained by gold-catalyzed chemical etching. The interplay between silicon and gold nanostructures is investigated by photoluminescence spectroscopy upon continuous and pulsed excitation, both at room and low temperature. Comparison with reference samples, obtained removing gold particles by selective etching, highlights an enhanced emission in samples containing silicon and gold nanoparticles, explained in terms of both surface modifications and optical coupling between emitting nanocrystals and nanoparticles featuring localized plasmon resonances.