Plasmonic Nanosponges Filled by Silicon for Enhanced White Light Emission

Nanoscale. 2020. Vol. 12. P. 1013–1021.

Larin A. O., Nomine A., Ageev E. I., Ghanbaja J., Kolotova L., Starikov S. V., Bruyere S., Belmonte T., Makarov S. V., Zuev D. A.

Plasmonic nanosponges are a powerful platform for various nanophotonic applications owing to extremely

high local field enhancement in metallic nanopores. The filling of the nanopores with high-refractive

index semiconductors (e.g. Si, Ge, GaP, etc.) opens up opportunities for the enhancement of nonlinear

effects in these materials. However, this task remains challenging due to the lack of knowledge on the

integration process of metal and high-index semiconductor components in such nanoobjects. Here, we

investigate metal-dielectric nanoparticles fabricated from bilayer Si/Au films by the laser printing technique

via a combination of theoretical and experimental methods. We reveal that these hybrid nanoparticles

represent the Au sponge-like nanostructure filled with Si nanocrystallites. We also demonstrate

that the Au net provides strong near-field enhancement in the Si grains increasing the white light photoluminescence

in the hybrid nanostructures compared to uniform Si nanoparticles. These results pave the

way for engineering the internal structure of the sponge-like hybrid nanoparticles possessing white light

luminescence and control of their optical properties on demand.

Keywords: nanosponges, Si/Au nanoparticles, наногубки, Si/Au наночастицы