Ultra-Wideband Wavelength Cross-Connect Switch Based on 300-mm Silicon Photonics

Silicon photonics switches are a promising solution for high-capacity, energy efficient, and highly integrated switching for datacenter networks and AI/ML clusters. Use of wideband wavelength division multiplexing (WDM) will be essential to increase the bandwidth density in the order of Tbps/mm. Wavelength cross-connect (WXC) chiplets will then be a key element for flexible networking of many wavelength channels over a wide wavelength range. In this paper, we review recent progress in silicon photonics switch technologies and 300-mm silicon photonics. We then show ultra-wideband (O-band to L-band) filtering operations of FSR-free grating-assisted contra-directional couplers (C-DCs) that we proposed for the WXC chiplets. Furthermore, we demonstrate a 32-Gbaud QPSK signal transmission of our 16 × 16 and 16-channel silicon photonics WXC switch realized by the silicon photonics switches and the C-DCs.