  In this work, we study the angular momentum transfer from a single swift
electron to non-spherical metallic nanoparticles, specifically investigating
spheroidal and polyhedral (Platonic Solids) shapes. While previous research has
predominantly focused on spherical nanoparticles, our work expands the
knowledge by exploring various geometries. Employing classical electrodynamics
and the small particle limit, we calculate the angular momentum transfer by
integrating the spectral density, ensuring causality through Fourier-transform
analysis. Our findings demonstrate that prolate spheroidal nanoparticles
exhibit a single blueshifted plasmonic resonance, compared to spherical
nanoparticles of equivalent volume, resulting in lower angular momentum
transfer. Conversely, oblate nanoparticles display two resonances (one
blueshifted and one redshifted) resulting in a higher angular momentum transfer
than their spherical counterparts. Additionally, Platonic Solids with fewer
faces exhibit significant redshifts in plasmonic resonances, leading to higher
angular momentum transfer due to edge effects. We also observe resonances and
angular momentum transfers with similar characteristics in specific pairs of
Platonic Solids, known as duals. These results highlight promising
applications, particularly in electron tweezers technology.
