Characterizing Localized Surface Plasmons Using Electron Energy-Loss Spectroscopy

Abstract

Electron energy-loss spectroscopy (EELS) offers a window to view nanoscale properties and processes. When performed in a scanning transmission electron microscope, EELS can simultaneously render images of nanoscale objects with sub-nanometer spatial resolution and correlate them with spectroscopic information of ∼ 10 − 100 meV spectral resolution. Consequently, EELS is a nearperfect tool for understanding the optical and electronic properties of individual and few-particle plasmonic metal nanoparticles assemblies, which are significant in a wide range of fields. This review presents an overview of basic plasmonics and EELS theory and highlights several recent noteworthy experiments involving the electron-beam interrogation of plasmonic metal nanoparticle systems.

Plasmon 3D Electron Tomography and Local Electric-Field Enhancement of Engineered Plasmonic Nanoantennas

“…In STEM-EELS, the electron beam is used to both excite and measure, and then EELS reflects the magnitude of the induced electric field at the location of the sub-nanometer electron beam. It is also claimed that no qualitative difference is observed between STEM-EELS maps of LSPR modes and electric field enhancement for particles with edges and corners 28 . Further, most work in correlating STEM-EELS and LSPR has been done on nanoparticles or flat metal patterns.…”

Detection of electron tunneling across plasmonic nanoparticle–film junctions using nitrile vibrations

“…Experimentally, this typically involves transmission electron microscopy (TEM) and indirect approaches such as electron energy loss spectroscopy (EELS) 20, 21 or surface-enhanced Raman scattering (SERS) 22 . Based on experimentally determined geometries, electric fields can be calculated and compared with the EELS results, although caution must be taken when correlating the EELS mode maps with the plane-wave induced electric fields.…”

Nanoscale mapping of optical band gaps using monochromated electron energy loss spectroscopy

“…Here we monitor the energy loss of a monochromatic electron beam due to excitation processes in the sample. Taking advantage of the high spatial resolution of the electron beam, mapping of the local geometries of systems and their optical response through surface plasmon polaritons and localized surface plasmons [12][13][14], and band gap excitations can be performed [15][16][17][18][19].…”