On-chip silicon photonic 2 × 2 mode- and polarization-selective switch with low inter-modal crosstalk

Abstract

Mode- and polarization-division multiplexing offer new dimensions to increase the transmission capacity of optical communications. Selective switches are key components in reconfigurable optical network nodes. An on-chip silicon 2×2 mode- and polarization-selective switch that can route four data channels on two modes and two polarizations simultaneously is proposed and experimentally demonstrated for the first time, to the best of our knowledge. The overall insertion losses are lower than 8.6 dB. To reduce the inter-modal crosstalk, polarization beam splitters are added to filter the undesired polarizations or modes. The measured inter-modal and intra-modal crosstalk values are below −23.2 and −22.8  dB for all the channels, respectively.