Nanooptical study of plasmonic antennas with fast electrons

Plasmonic devices such as optical antennas, operating in the visible region of the electromagnetic spectrum are constrained to spatial dimensions of a few nm to hundreds of nm. As most of the physical properties of the plasmons vary on a very short scale, it is necessary to study this  type of objects at the nanometer scale. We have performed Electron energy Loss Spectroscopy (EELS) spectral imaging in the IR-vis-UV regime in a Scanning Transmission Electron Microscope (STEM) on several types of coupled and uncoupled nanorods, either lithographed or chemically grown.