2025/10/20 by Yining Xuan, Xuan, Yining, Miyazaki, Daito +3
Engineering · Materials Science · Physics and Astronomy · #FOS: Physical sciences #Metamaterials and Metasurfaces Applications #Orbital Angular Momentum in Optics #Plasmonic and Surface Plasmon Research #Quantum Physics (quant-ph)
paper · pdf · doi:10.48550/arxiv.2510.18166
openalex publication_date 2025/10/20 · openalex created_date 2025/10/24 · openalex updated_date 2026/07/28
We demonstrate that non-chiral nanoparticles can produce chiral light when point emitters are coupled to their surface plasmon modes (SPMs) under certain conditions. Chiral emission arises from asymmetrical plasmon mode propagation from the source combined with the spin-momentum locked nature of the SPMs. The Purcell regime of cavity quantum electrodynamics (QED) ensures that radiation from the coupled mode dominates over that from the emitter itself, giving rise to photons with a circularly polarized component -- i.e. chiral light. We experimentally demonstrate this effect using electron beam-induced cathode luminescence from a gold nanorod, coupling it evanescently to a nanofiber probe which also supports spin-momentum locked light. This converts the net spin of the emission into a net directionality of propagation in the fiber modes.