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arXiv · 2203.00852

Preserving multi-level quantum coherence by dynamical decoupling

Xinxing Yuan·Yue Li·Mengxiang Zhang·Chang Liu·Mingdong Zhu·Xi Qin·Nikolay V. Vitanov·Yiheng Lin·Jiangfeng Du
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Abstract

Quantum information processing with multi-level systems (qudits) provides additional features and applications than the two-level systems. However, qudits are more prone to dephasing and dynamical decoupling for qudits has never been experimentally demonstrated. Here, as a proof-of-principle demonstration, we experimentally apply dynamical decoupling to protect superpositions with three levels of a trapped $^9\rm{Be}^+$ ion from ambient noisy magnetic field, prolonging coherence by up to approximately an order of magnitude. Our demonstration, straightforwardly scalable to more levels, may open up a path toward long coherence quantum memory, metrology and information processing with qudits.

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Xinxing Yuan, Yue Li, Mengxiang Zhang, Chang Liu, Mingdong Zhu, Xi Qin, Nikolay V. Vitanov, Yiheng Lin, Jiangfeng Du. 2022-03-02. Preserving multi-level quantum coherence by dynamical decoupling. https://doi.org/10.1103/physreva.106.022412

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