Radiationless anapole states in on-chip photonics

E. Díaz-Escobar, T. Bauer, E. Pinilla-Cienfuegos, A. I. Barreda, A. Griol, L. Kuipers and A. Martínez
Light: Science & Applications, 10, 204 (2021). https://doi.org/10.1038/s41377-021-00647-x

Enhanced on-chip photonic sensing and routing is playing an increasingly significant role in modern society. Realized as interference between different modes in high-index nanoparticles, radiationless states called anapoles are here one promising concept that combines reduced scattering with enhanced concentration of energy. Together with researchers from the Universitat Politècnica de València, Spain and the Friedrich Schiller University Jena, Germany, we now showed that when driven via integrated waveguides, these two striking properties decouple spectrally. The findings provide a crucial step towards the use of anapole states in photonic integrated circuitry.

For an in-depth discussion of the results, feel free to read this pdf!

Decoupling of anapole condition and near-field energy maximum in on-chip excitation of high-index nanodisks, with an experimental visualisation of the double-vortex structure of the contributing toroidal moment.