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arXiv · 1703.06613

Solving Systems of Linear Equations with a Superconducting Quantum Processor

Yarui Zheng·Chao Song·Ming-Cheng Chen·Benxiang Xia·Wuxin Liu·Qiujiang Guo·Libo Zhang·Da Xu·Hui Deng·Keqiang Huang·Yulin Wu·Zhiguang Yan·Dongning Zheng·Li Lu·Jian-Wei Pan·H. Wang·Chao-Yang Lu·Xiaobo Zhu
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Abstract

Superconducting quantum circuits are promising candidate for building scalable quantum computers. Here, we use a four-qubit superconducting quantum processor to solve a two-dimensional system of linear equations based on a quantum algorithm proposed by Harrow, Hassidim, and Lloyd [Phys. Rev. Lett. \textbf{103}, 150502 (2009)], which promises an exponential speedup over classical algorithms under certain circumstances. We benchmark the solver with quantum inputs and outputs, and characterize it by non-trace-preserving quantum process tomography, which yields a process fidelity of $0.837\pm0.006$. Our results highlight the potential of superconducting quantum circuits for applications in solving large-scale linear systems, a ubiquitous task in science and engineering.

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Yarui Zheng, Chao Song, Ming-Cheng Chen, Benxiang Xia, Wuxin Liu, Qiujiang Guo, Libo Zhang, Da Xu, Hui Deng, Keqiang Huang, Yulin Wu, Zhiguang Yan, Dongning Zheng, Li Lu, Jian-Wei Pan, H. Wang, Chao-Yang Lu, Xiaobo Zhu. 2017-03-20. Solving Systems of Linear Equations with a Superconducting Quantum Processor. https://doi.org/10.1103/physrevlett.118.210504

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