Exciting Magnetic Dipole Mode of Split Ring Plasmonic Nano Resonator by Photonic Crystal Nanocavity

TL;DR

This paper demonstrates a highly efficient method to excite magnetic dipole modes in split ring resonators on a chip by integrating them with photonic crystal nanocavities, enabling potential advances in integrated photonic devices.

Contribution

The study introduces a novel on-chip excitation technique for magnetic modes in plasmonic nanostructures using photonic crystal nanocavities, achieving high efficiency and tunability.

Findings

Achieved up to 58% excitation efficiency of magnetic dipole mode.

Demonstrated tuning of magnetic mode via positional and angular adjustments.

Proposed a hybrid structure with photonic crystal waveguide for future device integration.

Abstract

On chip exciting electric modes in individual plasmonic nanostructures are realized widely; nevertheless, the excitation of their magnetic counterparts is seldom reported. Here, we propose a highly efficient on chip excitation approach of the magnetic dipole mode of an individual split ring resonator (SRR) by integrating it onto a photonic crystal nanocavity (PCNC). A high excitation efficiency of up to 58% is realized through the resonant coupling between the modes of the SRR and PCNC. A further fine adjustment of the excited magnetic dipole mode is demonstrated by tuning the relative position and twist angle between the SRR and PCNC. Finally, a structure with a photonic crystal waveguide side coupled with the hybrid SRR PCNC is illustrated, which could excite the magnetic dipole mode with an in plane coupling geometry and potentially facilitate the future device application. Our result may open a way for developing chip integrated photonic devices employing a magnetic field component in the optical field.