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Optimal Strategies of Quantum Metrology with a Strict Hierarchy

Quantum Physics 2023-02-21 v3

Abstract

One of the main quests in quantum metrology is to attain the ultimate precision limit with given resources, where the resources are not only of the number of queries, but more importantly of the allowed strategies. With the same number of queries, the restrictions on the strategies constrain the achievable precision. In this work, we establish a systematic framework to identify the ultimate precision limit of different families of strategies, including the parallel, the sequential, and the indefinite-causal-order strategies, and provide an efficient algorithm that determines an optimal strategy within the family of strategies under consideration. With our framework, we show there exists a strict hierarchy of the precision limits for different families of strategies.

Keywords

Cite

@article{arxiv.2203.09758,
  title  = {Optimal Strategies of Quantum Metrology with a Strict Hierarchy},
  author = {Qiushi Liu and Zihao Hu and Haidong Yuan and Yuxiang Yang},
  journal= {arXiv preprint arXiv:2203.09758},
  year   = {2023}
}

Comments

6 + 23 pages, 10 figures; close to the published version