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arXiv · 2105.06074

Quantum Instruction Set Design for Performance

Cupjin Huang·Tenghui Wang·Feng Wu·Dawei Ding·Qi Ye·Linghang Kong·Fang Zhang·Xiaotong Ni·Zhijun Song·Yaoyun Shi·Hui-Hai Zhao·Chunqing Deng·Jianxin Chen
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Abstract

A quantum instruction set is where quantum hardware and software meet. We develop new characterization and compilation techniques for non-Clifford gates to accurately evaluate different quantum instruction set designs. We specifically apply them to our fluxonium processor that supports mainstream instruction $\mathrm{iSWAP}$ by calibrating and characterizing its square root $\mathrm{SQiSW}$. We measure a gate fidelity of up to $99.72\%$ with an average of $99.31\%$ and realize Haar random two-qubit gates using $\mathrm{SQiSW}$ with an average fidelity of $96.38\%$. This is an average error reduction of $41\%$ for the former and a $50\%$ reduction for the latter compared to using $\mathrm{iSWAP}$ on the same processor. This shows designing the quantum instruction set consisting of $\mathrm{SQiSW}$ and single-qubit gates on such platforms leads to a performance boost at almost no cost.

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Cupjin Huang, Tenghui Wang, Feng Wu, Dawei Ding, Qi Ye, Linghang Kong, Fang Zhang, Xiaotong Ni, Zhijun Song, Yaoyun Shi, Hui-Hai Zhao, Chunqing Deng, Jianxin Chen. 2021-05-13. Quantum Instruction Set Design for Performance. https://doi.org/10.1103/physrevlett.130.070601

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