Numerical simulation of split ring resonator near-fields and antiferromagnetic magnon hybridization

Abstract

We report on the results of finite difference time domain (FDTD) simulations of the terahertz response of a split ring resonator (SRR) metamaterial coupled to a hypothetical antiferromagnetic material (AFM) characterized by a magnon resonance. We find a hybridization of the SRR’s local magnetic field and the magnon, which manifests as an avoided crossing in the far-field transmission spectrum. We show that the strong light-matter coupling can be modelled via a two coupled oscillator model. We further evaluate the SRR-AFM coupling strength by varying the physical separation with a dielectric spacer between them. We find strong coupling for spacers thinner than 3 μm, suggesting far-field transmission measurements of metamaterial near-fields to be a versatile platform to investigate magnetic excitations of quantum materials.