Collectively driven optical nanoantennas

Optical nanoantennas, i.e., elements transforming localized light or waveguide modes into freely propagating fields and vice versa, are vital components for modern nanophotonics. antennas have been demonstrated to cause the Dicke superradiance effect, collective spontaneous emission of quantum sources. However, impact coherent excitation on antenna performance, such as directivity, efficiency, Purcell remains mostly unexplored. Herein, using full-wave numerical simulations backed by a model, we unveil that allows controlling multipoles, on-demand nonradiative states, enhanced improving radiation efficiency. This corresponds states with nonzero dipole moment in picture, where phase is well defined. The results this work bring another degree freedom----the an ensemble emitters----to control optical nanoantennas and, such, pave way use excitations nanophotonic devices superb performance. To make discussion independent frequency range, consider all-dielectric design dimensionless units.