Hybrid Toroidal Resonance Response in Planar Core-Shell THz Metasurfaces

Toroidal resonance of planar structure is feasible and interesting for many appealing applications. We numerically and experimentally investigated the toroidal resonances in a planar metamaterial comprising core-shell structures and its constituent core and shell components at THz frequencies. The investigated structure demonstrated sharp toroidal and hybrid toroidal resonance modes in 0.2-0.3 THz range. Our analysis showed that these modes could be explained by the interaction of resonance toroidal modes of the shell and core components. The response of the investigated planar core-shell toroidal metasurface is notably geometry dependent and can be easily tuned by tailoring the device geometry. Presented work can be used for advanced THz photonics applications, including precise bio-sensing, narrow-band filters, fast-switching, and modulation.

Automated summary

Toroidal resonance in planar core-shell structures at THz frequencies can exhibit sharp resonance modes, and the response is geometry dependent and can be tuned for applications such as precise bio-sensing and narrow-band filters.