Multi-FSR Silicon Photonic Flex-LIONS Module for Bandwidth-Reconfigurable All-to-All Optical Interconnects

This article proposes and experimentally demonstrates the first bandwidth-reconfigurable all-to-all optical interconnects using a multi-Free-Spectral-Ranges (FSR) integrated 8 × 8 SiPh Flex-LIONS module. The multi-FSR operation utilizes the first FSR (FSR1) to steer the bandwidth between selected node pairs and the zeroth FSR (FSR0) to guarantee a minimum diameter all-to-all topology among the interconnected nodes after reconfiguration. Successful Flex-LIONS design, fabrication, packaging, and system testing demonstrate error-free all-to-all interconnects for both FSR0 and FSR1 with a 5.3-dB power penalty induced by AWGR intra-band crosstalk under the worst-case polarization scenario. After reconfiguration in FSR1, the bandwidth between the selected pair of nodes is increased from 50 to 125 Gb/s while maintaining a 25 Gb/s/λ all-to-all interconnectivity in FSR0.