Xu Wenqu, Guo Tingting, Zhang Kaixuan, Li Zishuo, Zhou Tianshi, Zuo Quan, Sheng Yifan, Jing Lingxiao, Ma Huashi, Yu Mingyuan, Zhou Shunhong, Li Binglin, Yang Shiyao, Yu Yongyang, Zhang Junzhou, Zhu Jiyuan, Cao Chunhai, Zhu Guanghao, Sun Guozhu, Wu Peiheng
Research Institute of Superconductor Electronics, School of Electronic Science and Engineering, Nanjing University, Nanjing, China.
Purple Mountain Laboratories, Nanjing, China.
Nat Commun. 2025 Mar 17;16(1):2629. doi: 10.1038/s41467-025-57820-8.
In recent years, significant progress has been made in the field of superconducting quantum circuits, particularly in improving the complexity of quantum processors for large-scale quantum computing and quantum simulation tasks. To enable the execution of quantum information processing tasks on large-scale quantum circuits containing millions of qubits, it is essential to minimize thermal effects on control and measurement lines, ensuring that circuit components are superconducting and that qubits are not significantly thermally excited. Recent studies have shown that a quadrature-biased electro-optic fiber link can operate qubits with a much reduced thermal load, thereby facilitating the simultaneous operation of a large number of qubits. Expanding on this, here we propose and demonstrate that coherent manipulations of superconducting qubits can also be achieved by setting the bias point of the electro-optic modulator at the null point instead of the quadrature point. Major advantages of our null-point bias method include further reduction of the thermal load and improvement of the signal-to-noise ratio, and relaxed requirement for experimental implementations. Simultaneous control of two qubits is also demonstrated using the proposed null-biased fiber-optic link, which is the first time to the best of our knowledge.
近年来，超导量子电路领域取得了重大进展，特别是在提高用于大规模量子计算和量子模拟任务的量子处理器的复杂性方面。为了在包含数百万个量子比特的大规模量子电路上执行量子信息处理任务，必须将热效应降至最低，确保控制和测量线路上的电路组件处于超导状态，并且量子比特不会受到显著的热激发。最近的研究表明，正交偏置电光光纤链路可以在热负载大幅降低的情况下操作量子比特，从而便于大量量子比特同时运行。在此基础上，我们提出并证明，通过将电光调制器的偏置点设置在零点而非正交点，也可以实现超导量子比特的相干操纵。我们的零点偏置方法的主要优点包括进一步降低热负载、提高信噪比以及放宽实验实施要求。我们还使用所提出的零偏置光纤链路演示了对两个量子比特的同时控制，据我们所知这是首次实现。
