Near field characterization of plasmonic nanostructures with electron energy loss spectroscopy

Abstract

Electron energy loss spectroscopy (EELS) in combination with scanning transmission electron microscopy (STEM) was used to characterize the near field distribution of plasmonic nanostructures. The results were compared to optical experiments as well as numerical simulations. This work focuses on the near field properties of split-ring resonators (SRRs), which are one of the most prominent examples of metamaterials. The main results of this thesis are: <br /> (i) Proof of Babinet's principle in the near-infrared and visible regime,<br /> (ii) visualization of bright and dark modes in coupled nanoparticles, and <br /> (iii) a three dimensional analysis of the plasmonic near field of an individual SRR.