Design of plasmonic directional antennas via evolutionary optimization

Abstract

We demonstrate inverse design of plasmonic nanoantennas for directional light\nscattering. Our method is based on a combination of full-field electrodynamical\nsimulations via the Green dyadic method and evolutionary optimization (EO).\nWithout any initial bias, we find that the geometries reproducibly found by EO,\nwork on the same principles as radio-frequency antennas. We demonstrate the\nversatility of our approach by designing various directional optical antennas\nfor different scattering problems. EO based nanoantenna design has tremendous\npotential for a multitude of applications like nano-scale information routing\nand processing or single-molecule spectroscopy. Furthermore, EO can help to\nderive general design rules and to identify inherent physical limitations for\nphotonic nanoparticles and metasurfaces.\n