Characterization of thin-film lithium niobate modulators at 298 K and 38.5 K

High-speed and energy-efficient cryogenic electronics in supercomputers and quantum computers have emerged as the most competitive alternative in the next generation of information processing systems. Specifically, the challenge of establishing broadband, energy-efficient data transmission from cryogenic electronics to room temperature environments has emerged as a significant bottleneck. Electro-optic data links based on the thin-film lithium niobate (TFLN) electro-optic modulators (EOMs) operated at 38.5 K hold the potential to breakthrough this limitation by providing high bandwidth and low heat load for signal readout in cryogenic electronics. In this article, the performance of a TFLN EOM was examined at room temperature and cryogenic temperature, respectively. The results show that the system achieves a bandwidth of 7.6 GHz at 38.5 K, which is 7% higher than the bandwidth achieved at 298 K. A data transmission rate of 15 Gbps using non-return-to-zero (NRZ) encoding supporting error-free data transmission at 38.5 K to the error detector at 298 K is demonstrated as a viable solution for cryo-computing.