[16a-B4-1~9] 4.1 Plasmonics and Nanophotonics

9:00 AM - 9:30 AM JST(12:00 AM - 12:30 AM UTC)English Presentation

[16a-B4-1] [JSAP-Optica Joint Symposia Invited Talk] Electromagnetic Asymmetry, Quantum Conductivity and Optical Magnetism for Nonlinear Plasmonics

〇Dangyuan Lei¹ (1.City Uni. of Hong Kong)

Keywords:

electromagnetic asymmetry,plasmonic nanocavity,second-harmonic generation

In general, symmetric plasmonic nanocavities, such as a pair of two closely spaced metal nanospheres of the same size and constituting material, support only symmetry-allowed bright modes under light illumination. Breaking the cavity symmetry introduces mode hybridization between its bright and dark modes, leading to new plasmon modes like Fano resonance and bound states in the continuum.

In this talk, I will go on to discuss three “dark” aspects of symmetry-broken plasmonic nanocavities, including 1) light-induced electromagnetic asymmetry for enhancing the surface second-harmonic generation (SHG) of noble metals (Nature Communications 2021, 12, 4326), a mechanism well beyond conventional enhancement strategies, 2) photon-assisted tunnelling induced second-order nonlinear optics in conductive molecular nano-junctions (Nano Letters 2023, 23(12), 5851-5858), and 3) plasmon-induced optical magnetism in an asymmetric nanoparticle dimer-on-mirror cavity and its theoretical implication as a new second-order nonlinear source (Laser & Photonics Reviews 2020, 14(9), 200068).