摘要
High-fidelity two-qubit gates are essential for the realization of large-scale quantum computation and simulation.Tunable coupler design is used to reduce the problem of parasitic coupling and frequency crowding in manyqubit systems and thus thought to be advantageous. Here we design an extensible 5-qubit system in which center transmon qubit can couple to every four near-neighboring qubits via a capacitive tunable coupler and experimentally demonstrate high-fidelity controlled-phase(CZ) gate by manipulating central qubit and one nearneighboring qubit. Speckle purity benchmarking and cross entropy benchmarking are used to assess the purity fidelity and the fidelity of the CZ gate. The average purity fidelity of the CZ gate is 99.69±0.04% and the average fidelity of the CZ gate is 99.65±0.04%, which means that the control error is about 0.04%. Our work is helpful for resolving many challenges in implementation of large-scale quantum systems.
作者
Yangsen Ye
Sirui Cao
Yulin Wu
Xiawei Chen
Qingling Zhu
Shaowei Li
Fusheng Chen
Ming Gong
Chen Zha
He-Liang Huang
Youwei Zhao
Shiyu Wang
Shaojun Guo
Haoran Qian
Futian Liang
Jin Lin
Yu Xu
Cheng Guo
Lihua Sun
Na Li
Hui Deng
Xiaobo Zhu
Jian-Wei Pan
叶杨森;曹思睿;吴玉林;陈厦微;朱庆玲;李少炜;陈福升;龚明;查辰;黄合良;赵有为;王石宇;郭少俊;钱浩然;梁福田;林金;徐昱;郭成;孙丽华;李娜;邓辉;朱晓波;潘建伟(Hefei National Laboratory for Physical Sciences at the Microscale and Department of Modern Physics,University of Science and Technology of China,Hefei 230026,China;Shanghai Branch,CAS Center for Excellence in Quantum Information and Quantum Physics,University of Science and Technology of China,Shanghai 201315,China;Shanghai Research Center for Quantum Sciences,Shanghai 201315,China;Henan Key Laboratory of Quantum Information and Cryptography,Zhengzhou 450000,China)
基金
the National Key R&D Program of China(Grant No.2017YFA0304300)
the Chinese Academy of Sciences
Anhui Initiative in Quantum Information Technologies
Technology Committee of Shanghai Municipality
the National Natural Science Foundation of China(Grants Nos.11905217,11774326,and 11905294)
the Shanghai Municipal Science and Technology Major Project(Grant No.2019SHZDZX01)
the Natural Science Foundation of Shanghai(Grant No.19ZR1462700)
the Key-Area Research and Development Program of Guangdong Provice(Grant No.2020B0303030001)
the Youth Talent Lifting Project(Grant No.2020-JCJQ-QT-030)。
