Fig. 1: Chiral plasmonic arrays design, gold colloids assembly, FDTD calculations, experimental g-factor and EELS characterization.

a Schematic representation of the designed single triskelion pattern and arranged in a hexagonal lattice. R = 200 nm, d = 75 nm, s = 15 nm, φ = 5°, LP = 500 nm. b Schematic representation of the fabrication process. FDTD calculated g-factor spectra for (c) 100 nm height bulk Au triskelia array, (d) modeled triskelia array composed of Au nanoparticles, and (e) experimental g-factor spectrum for 27 nm Au nanoparticles triskelia assembly. The insets in c, d depict the modeled structures. Whereas in e, an SEM image of the sample is shown. f Cross-section of the FDTD simulated electric field distribution for a single bulk Au triskelion. g EELS map in the energy range of 1.8–1.9 eV. h STEM image of the triskelion array on a TEM grid. Source data are provided as a Source Data file.