2015/10/09 by D. Ugarte, Daniel Ugarte, Caterina Ducati · 1 citation
Engineering · Materials Science · Physics and Astronomy · #Atomic physics #Condensed matter physics #Electron #Excitation #Gold and Silver Nanoparticles Synthesis and Applications #Molecular physics #Optics #Orbital Angular Momentum in Optics #Physics #Plasmon #Plasmonic and Surface Plasmon Research #Surface plasmon #Vortex #cond-mat.mtrl-sci
paper · pdf · doi:10.1103/physrevb.93.205418
arxiv created 2015/10/09 · openalex publication_date 2016/05/11 · arxiv updated 2016/05/25 · openalex created_date 2025/10/10 · openalex updated_date 2026/08/05
We have theoretically studied how the azimuthal phase structure of an electron vortex beam excites surface plasmons on metal particles of different geometries as observed in electron energy loss spectroscopy (EELS). We have developed a semiclassical approximation combining a ring-shaped beam and the dielectric formalism. Our results indicate that for the case of total orbital angular momentum transfer, we can manipulate surface plasmon multipole excitation and even attain an enhancement factor of several orders of magnitude. Since electron vortex beams interact with particles mostly through effects due to azimuthal symmetry, i.e., in the plane perpendicular to the electron beam, anisotropy information (longitudinal and transversal) of the sample may be derived in EELS studies by comparing nonvortex and vortex beam measurements.