Hardware-efficient and fast three-qubit gate in superconducting quantum circuits  

作　　者：Xiao-Le Li Ziyu Tao Kangyuan Yi Kai Luo Libo Zhang Yuxuan Zhou Song Liu Tongxing Yan Yuanzhen Chen Dapeng Yu 

机构地区：[1]Department of Physics,Harbin Institute of Technology,Harbin 150001,China [2]Department of Physics,Southern University of Science and Technology,Shenzhen 518055,China [3]Shenzhen Institute for Quantum Science and Engineering,Southern University of Science and Technology,Shenzhen 518055,China [4]Shenzhen International Quantum Academy(SIQA),Shenzhen 518048,China [5]Guangdong Provincial Key Laboratory of Quantum Science and Engineering,Southern University of Science and Technology,Shenzhen 518055,China

出　　处：《Frontiers of physics》2024年第5期185-191,共7页物理学前沿（英文版）

基　　金：supported by the Key-Area Research and Development Program of Guangdong Province(No.2018B030326001);the National Natural Science Foundation of China(Nos.12074166 and 12004162);the Guangdong Provincial Key Laboratory(No.2019B121203002).

摘　　要：While the common practice of decomposing general quantum algorithms into a collection of single-and two-qubit gates is conceptually simple,in many cases it is possible to have more efficient solutions where quantum gates engaging multiple qubits are used.In the noisy intermediate-scale quantum(NISQ)era where a universal error correction is still unavailable,this strategy is particularly appealing since it can significantly reduce the computational resources required for executing quantum algorithms.In this work,we experimentally investigate a three-qubit ControlledCPHASE-SWAP(CCZS)gate on superconducting quantum circuits.By exploiting the higher energy levels of superconducting qubits,we are able to realize a Fredkin-like CCZS gate with a duration of 40 ns,which is comparable to typical single-and two-qubit gates realized on the same platform.By performing quantum process tomography for the two target qubits,we obtain a process fidelity of86.0%and 81.1%for the control qubit being prepared in|0>and|1>,respectively.We also show that our scheme can be readily extended to realize a general CCZS gate with an arbitrary swap angle.The results reported here provide valuable additions to the toolbox for achieving large-scale hardware-efficient quantum circuits.

关 键 词：quantum computation quantum gate superconducting circuit 

分 类 号：O413[理学—理论物理]