Anapoles in dielectric metasurfaces and thermal tunabilty: theory and experiments

We present the theoretical and experimental investigation of a thermally tunable all-dielectric metasurface that sustains the non-radiating anapole source. The metasurface consists of high index metaatoms arranged in a regular pentagon with properly adjusted parameters such that the toroidal and electric dipole excitation lead to a destructive interference in the far-field. For the experimental realization we use PVC tubes of millimeter diameter that are filled with water. We place the metaatom inside a rectangular microwave waveguide and with the use of a heating belt we modify the water optical properties and measure the corresponding scattering spectra. Our findings demonstrate a wide tunability in the response of the metasurface and reveal the sensitivity of the anapole state to material losses.

Automated summary

This study presents a theoretical and experimental investigation of a thermally tunable all-dielectric metasurface sustaining a non-radiating anapole source. Using PVC tubes filled with water for the experimental realization, the metasurface shows wide tunability in response and sensitivity of the anapole state to material losses was revealed.