Large-Scale Inverse Design of a Planar On-Chip Mode Sorter

Spatial modes of light can be used as carriers information in classical optical communication or an alphabet quantum communication. In order to exploit the spatial domain, it is required (de)multiplex different from a shared input channel into output ports. Mode sorters have been employed free-space and fiber systems but date not realized for planar guided waves. Here we present general method compact on-chip sorting beams with micrometric footprint nanometric thickness. The designs were generated using linkage-tree-based genetic algorithm experimentally demonstrated on surface plasmon polariton platform by Hermite–Gaussian beams. here readily applied optimize complex, large-scale devices involving beam propagation methods.