Electronic-Photonic Cryogenic Egress Link

A novel coherent optical link is proposed to serve as the interconnection technology between the room temperature and cryogenic temperature environment for quantum computing and high-performance superconducting computing. The tradeoff on the energy efficiency of this link is discussed. A prototype optical transmitter is fabricated in the 45RFSOI CMOS process and characterized at the cryogenic temperature. Measurement results show that this optical transmitter is able to be directly driven by superconducting electronics with millivolt-level voltage swing, and the new link has five times better energy efficiency than the traditional intensity modulation, direct-detection link.