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arXiv · 2212.02831

99.92%-Fidelity CNOT Gates in Solids by Filtering Time-dependent and Quantum Noises

Tianyu Xie·Zhiyuan Zhao·Shaoyi Xu·Xi Kong·Zhiping Yang·Mengqi Wang·Ya Wang·Fazhan Shi·Jiangfeng Du
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Abstract

Inevitable interactions with the reservoir largely degrade the performance of non-local gates, which hinders practical quantum computation from coming into existence. Here we experimentally demonstrate a 99.920(7)\%-fidelity controlled-NOT gate by suppressing the complicated noise in a solid-state spin system at room temperature. We found that the fidelity limited at 99\% in previous works results from only considering static noise, and thus, in this work, time-dependent noise and quantum noise are also included. All noises are dynamically corrected by an exquisitely designed shaped pulse, giving the resulting error below $10^{-4}$. The residual gate error is mainly originated from the longitudinal relaxation and the waveform distortion that can both be further reduced technically. Our noise-resistant method is universal, and will benefit other solid-state spin systems.

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Tianyu Xie, Zhiyuan Zhao, Shaoyi Xu, Xi Kong, Zhiping Yang, Mengqi Wang, Ya Wang, Fazhan Shi, Jiangfeng Du. 2022-12-06. 99.92%-Fidelity CNOT Gates in Solids by Filtering Time-dependent and Quantum Noises. https://arxiv.org/abs/2212.02831

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