Compact metallo-dielectric hybrid clusters with subwavelength dimensions are fabricated by template guided self-assembly. Elastic and inelastic scattering spectroscopy and electromagnetic simulations reveal that hybrid clusters comprising TiO(2) nanoparticles on top of a cluster of strongly coupled gold nanoparticles harness synergistic electromagnetic interactions between the building blocks. This results in a boost of the peak electric field intensity and a redistribution of the field in the ambient medium. The complex phase landscape in the clusters features optical vortices that enhance the magnetic field.
Hong, Y., Pourmand, M., Boriskina, S. V., & Reinhard, B. M. (2013). Enhanced light focusing in self-assembled optoplasmonic clusters with subwavelength dimensions. Advanced Materials, 25(1), 115–119. https://doi.org/10.1002/adma.201202830