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arXiv · 1303.3437

Criterion on remote clocks synchronization within a Heisenberg scaling accuracy

Yong-Liang Zhang·Yu-Ran Zhang·Liang-Zhu Mu·Heng Fan
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Abstract

We propose a quantum method to judge whether two spatially separated clocks have been synchronized within a specific accuracy $σ$. If the measurement result of the experiment is obviously a nonzero value, the time difference between two clocks is smaller than $σ$; otherwise the difference is beyond $σ$. On sharing the 2$N$-qubit bipartite maximally entangled state in this scheme, the accuracy of judgement can be enhanced to $σ\simπ/{(ω(N+1))}$. This criterion is consistent with Heisenberg scaling that can be considered as beating standard quantum limit, moreover, the unbiased estimation condition is not necessary.

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Yong-Liang Zhang, Yu-Ran Zhang, Liang-Zhu Mu, Heng Fan. 2013-03-17. Criterion on remote clocks synchronization within a Heisenberg scaling accuracy. https://doi.org/10.1103/physreva.88.052314

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