Surface plasmon excitation via Au nanoparticles in n-CdSe/p-Si heterojunction diodes

We report on the significant enhancement of photocurrent in pn heterojunction diode, consisting of n-CdSe/p-Si substrates, in situ deposited with Au nanoparticles on the surface by the pulsed-laser deposition technique. This is attributed due to the large enhancement in electromagnetic field that occurs in the vicinity of the metal surface, causing surface plasmons. The large enhancement in Raman and photoluminescence intensity was observed due to surface plasmon resonance. Our results suggest that the photodetectors, optoelectronic, such as high-performance thin-film solar cells, optical communication, and sensing devices, including bio- and molecular sensors, can be fabricated with improved functionality.