Origin of the chiral plasmonic behaviour in 3D helix based nanostructures

The nanoscaling of metallic helix, to operate at the visible frequency, enables the plasmonic effect to come into play. Here, we discuss the origin of plasmonic resonances in the composite carbon-platinum alloy nanohelices fabricated by deposition induced by focused ion beam (FIBID) and the chiro-optical property dependence on the 3D spatial helical arrangement.