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arXiv · 2112.14922

Scalable algorithm simplification using quantum AND logic

Abstract

Implementing quantum algorithms on realistic hardware requires translating high-level global operations into sequences of native elementary gates, a process known as quantum compiling. Physical limitations, such as constraints in connectivity and gate alphabets, often result in unacceptable implementation costs. To enable successful near-term applications, it is crucial to optimize compilation by exploiting the potential capabilities of existing hardware. Here, we implement a resource-efficient construction for a quantum version of AND logic that can reduce the cost, enabling the execution of key quantum circuits. On a high-scalability superconducting quantum processor, we demonstrate low-depth synthesis of high-fidelity generalized Toffoli gates with up to 8 qubits and Grover's search algorithm in a search space of up to 64 entries; both are the largest such implementations in scale to date. Our experimental demonstration illustrates a scalable implementation of simplifying quantum algorithms, paving the way for larger, more meaningful quantum applications on noisy devices.

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Ji Chu, Xiaoyu He, Yuxuan Zhou, Jiahao Yuan, Libo Zhang, Qihao Guo, Yongju Hai, Zhikun Han, Chang-Kang Hu, Wenhui Huang, Hao Jia, Dawei Jiao, Yang Liu, Zhongchu Ni, Xianchuang Pan, Jiawei Qiu, Weiwei Wei, Zusheng Yang, Jiajian Zhang, Zhida Zhang, Wanjing Zou, Yuanzhen Chen, Xiaowei Deng, Xiuhao Deng, Ling Hu, Jian Li, Dian Tan, Yuan Xu, Tongxing Yan, Xiaoming Sun, Fei Yan, Dapeng Yu. 2021-12-30. Scalable algorithm simplification using quantum AND logic. https://doi.org/10.1038/s41567-022-01813-7

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