Three-dimensional plasmonic nano-router via optical antennas

Abstract

Abstract A three-dimensional (3D) nanoscale optical router is a much-desired component in 3D stacked optical integrated circuits. However, existing 3D routers based on dielectric configurations suffer from large footprints and nanoscale routers based on plasmonic antennas only work in a 2D in-plane scene. Here, we propose and experimentally demonstrate cross-layered all-optical 3D routers with nanoscale footprints. Optical slot antenna pairs are used to realize the routing of plasmonic signals between different layers for arbitrary direction in a broadband wavelength range. The routers are also integrated with waveguide directly for exploring further applications. Based on these router elements, a 3D network of optical butterfly interconnection is demonstrated for multi-directional all-optical data communication. The proposed configuration paves the way for optical cross-layer routing on the nanoscale and advances the research and applications for 3D plasmonic circuits with high integration density in the future.