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arXiv · 2404.13317

Unambiguous discrimination of general quantum operations

Weizhou Cai·Jing-Ning Zhang·Ziyue Hua·Weiting Wang·Xiaoxuan Pan·Xinyu Liu·Yuwei Ma·Ling Hu·Xianghao Mu·Haiyan Wang·Yipu Song·Chang-Ling Zou·Luyan Sun
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Abstract

The discrimination of quantum operations has long been an intriguing challenge, with theoretical research significantly advancing our understanding of the quantum features in discriminating quantum objects. This challenge is closely related to the discrimination of quantum states, and proof-of-principle demonstrations of the latter have already been realized using optical photons. However, the experimental demonstration of discriminating general quantum operations, including both unitary and non-unitary operations, has remained elusive. In general quantum systems, especially those with high dimensions, the preparation of arbitrary quantum states and the implementation of arbitrary quantum operations and generalized measurements are non-trivial tasks. Here, for the first time, we experimentally demonstrate the optimal unambiguous discrimination of up to 6 displacement operators and the unambiguous discrimination of non-unitary quantum operations. Our results demonstrate powerful tools for experimental research in quantum information processing and are expected to stimulate a wide range of valuable applications in the field of quantum sensing.

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Weizhou Cai, Jing-Ning Zhang, Ziyue Hua, Weiting Wang, Xiaoxuan Pan, Xinyu Liu, Yuwei Ma, Ling Hu, Xianghao Mu, Haiyan Wang, Yipu Song, Chang-Ling Zou, Luyan Sun. 2024-04-20. Unambiguous discrimination of general quantum operations. https://doi.org/10.1126/sciadv.adq2529

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