Direct on-Chip Optical Communication between Nano Optoelectronic Devices

On-chip optical communication between individual nano optoelectronic components is important to reduce the footprint and improve energy efficiency of photonic neuromorphic solutions. Although nanoscale photon emitters and receivers have been reported separately, communication between them remains largely unexplored. We demonstrate direct on-chip directional broadcasting of light between individual InP nanowire photodiodes on silicon. The performance of multiple wire-to-wire communication circuits is mapped, demonstrating robust performance with up to 5 bit resolution as needed in biological networks and a minimum component driving power for continuous operation of 0.5 μW which is below that of conventional hardware. The results agree well with theoretical modeling that allows us to understand network performance limits and identify where significant improvements could be achieved. We estimate that an energy per operation of ∼1 fJ and signal fan-out from one emitter to hundreds of other nodes is possible. We find that the nanowire circuit performance parameters can satisfy the quantitative requirements to run the tasks of neural nodes in a bioderived neural network for autonomous navigation.