Demonstration of Compact Silicon Nitride Grating Coupler Arrays for Fan-out of Multicore Fibers

We propose a compact on-chip fan-out for multicore fiber using a focusing grating coupler array realized on a single-etch silicon nitride platform. Coupling loss of 11 dB with a 3-dB bandwidth of 30 nm and channel crosstalk lower than 28 dB are demonstrated.