Controllable optical resonances and unidirectional scattering by core-shell nanoparticles. Issue 2 (April 2021)

• Record Type: Journal Article
• Authors: Dong, Yiwei; Yang, Yuanqing
• Is Part Of: Journal of physics. Volume 1865:Issue 2(2021)
• Publication Date: 2021-04
• Subjects: Mie scattering -- electrical and magnetic resonance -- Kerker condition -- unidirectional scattering; Physics -- Congresses; 530.5
• DOI: 10.1088/1742-6596/1865/2/022045
• Languages: English
• ISSNs: 1742-6588

Abstract

Abstract: Nanoparticles supporting a distinct series of Mie resonances have enabled a new class of nanoantennas and provide efficient ways to manipulate light at the nanoscale. The ability to flexibly tune the optical resonances and scattering directionality are particularly essential for various applications ranging from biosensing to nanolasers. In this paper, we investigate the core-shell nanoparticles that support both electric and magnetic Mie resonances and for the first time systematically reveal the mode evolution from a pure high-index dielectric nanosphere to its plasmonic counterpart. Abrupt mode transition and hybridization of Mie resonances are found in Ag-dielectric core-shell spheres when core-shell ratio increases from 0.4 to 0.5. Furthermore, by engineering the electric and magnetic resonances, we demonstrate the unidirectional forward and backward scattering in such a system and reveal its tunability via geometric tuning.