All-Photonic Magnetic Resonance in Silicon Nanoparticles

All-photonic response in Silicon (Si) nanoparticles is dominated by magnetic resonance, leading to enhance light concentration for energy harvesting and magnetic imaging applications. The resonance phenomena occur when the natural frequency of the system matches external excitation and is well-explained by linear circuit analysis. In this paper, we propose a spherical wave impedance approach by employing the basic concept of impedance known at microwave frequencies, where it is defined as the ratio of the electric and magnetic fields to derive necessary magnetic resonance conditions. The model is used to derive various cross-section efficiencies, with results showing close agreement with the Mie solution. The proposed model is simple and compact and defines the resonance phenomena in Si nanoparticles using lumped circuit components, which is necessary for the large-scale all-photonic application of magnetic resonance using dielectric nanoparticles.