Collective resonances in a circular array of gyromagnetic rods

Jin Wang, Kai Fung Lee, Hui Yuan Dong, Zheng Gao Dong, S. F. Yu, Kin Hung Fung (Corresponding Author)

Research output: Journal article publicationJournal articleAcademic researchpeer-review

Abstract

We present a rigorous theoretical investigation on the collective magnetic resonance of a circular array of subwavelength gyromagnetic rods. We derive the closed-form solutions to the eigenmodes within the framework of the dynamic dipole approximation using an eigenresponse theory. Owing to the lack of time-reversal symmetry and Lorentz reciprocity, the eigenpolarizability spectra exhibit significant nonreciprocal characteristics: only a single branch of rotating magnetic dipoles is supported, whereas another one corresponding to inversely rotating magnetic dipoles is totally suppressed. We found that the collective coupled magnetic dipole and coupled electric dipole (CED) modes of the circular arrays display remarkable distinction in both the resonant frequency and the radiative width in comparison with the isolated gyromagnetic rod. We further carry out full-wave numerical simulation to test the accuracy of the analytical results on the CED mode.

Original languageEnglish
Article number045425
JournalPhysical Review B
Volume101
Issue number4
DOIs
Publication statusPublished - 21 Jan 2020

ASJC Scopus subject areas

  • Electronic, Optical and Magnetic Materials
  • Condensed Matter Physics

Cite this