1.28 Terabit-per-second all-silicon avalanche receiver

Abstract

To meet the exponential growth in data traffic, silicon (Si) photonics has emerged as a promising technology for ultra-high-speed and low-cost optical interconnects. However, achieving high-performance photodetectors (PDs) on Si photonics requires integrating narrower-bandgap materials, resulting in more complex fabrication processes, higher cost, and yield issues. To address this challenge, we demonstrate an all-Si solution showing a cost-efficient 8-channel double-microring resonator (MRR) avalanche photodiode (APD)-based receiver (RX) with an aggregate data rate of 1.28 Tb/s. All channels show excellent uniformity in their device performance with a responsivity of 0.4 A/W, an ultra-low dark current of 1 nA, a high bandwidth of 40 GHz, and a 𝑘 value of 0.28. To the best of our knowledge, this is the first demonstration of an all-Si RX supporting a record-high transmission data rate of 160 Gb/s per channel, along with ultralow electrical crosstalk of < -50 dB. This all Si optical RX can compete with the commercial heterojunction-based RXs and promises ~ 40% chip cost saving, thus paving the way to realize >3.2 Tb/s interconnects for future optical networks.