We investigate the chiroptical response of a single plasmonic nanohelix interacting with a weakly-focused circularly-polarized Gaussian beam. The optical scattering at the fundamental resonance is characterized experimentally, and the chiral behavior of the nanohelix is explained based on a multipole analysis. The angularly resolved emission of the excited nanohelix is verified experimentally and it validates the theoretical results. Further, we study the first higher-order resonance and explain the formation of chiral dipoles in both cases.
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