Investigation of near field enhancement in clusters of plasmonic non-spherical particles considering nonlocal effects

• Applicant: Dr.-Ing. Thomas Wriedt
• Subject Area: Mechanical Process Engineering
• Term: from 2017 to 2019
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 398165281

Plasmonics allows to manipulate light at the nanoscale and to obtain strong and very confined electromagnetic fields. This is achieved via a localized surface plasmon resonance, which is a well-known phenomenon that occurs in metal nanoparticles due to the collective oscillation of free electrons in nanosized structures when subjected to an incident electromagnetic field. The optical response of plasmonic nanostructures is generally well-described by classical electromagnetics relying on the use of local, frequency-dependent dielectric functions. If the structure size is less than 10 nm or there is a small curvature of the surface classical Maxwell's theory is no longer sufficient and a new approach is required going beyond classical electromagnetics to describe the occurring physical nonlocal effects. The objective of this project is to develop and test a nonlocal electromagnetics model for clusters of plasmonic nanoparticles for investigation of near field enhancement in clusters and near nanoparticles positioned on a plane surface. Both the nonlocal Hydrodynamic Drude model (HDD) and the Generalized Nonlocal Optical Response (GNOR) models will be implemented for clusters of nanoparticles in the frame of the Discrete Sources Method. The near field should especially be high near the plasmon resonance wavelength of the nanoparticle or the system of nanoparticles but its magnitude should be reduced considering nonlocal effects compared to classical electromagnetics. This research hypothesis will be tested by an extensive computational study.

• DFG Programme: Research Grants
• International Connection: Russia
• Cooperation Partner: Professor Dr. Yuri Eremin