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arXiv · 1403.1333

The Zeno limit in frequency estimation with non-Markovian environments

Katarzyna Macieszczak
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Abstract

We prove the Zeno limit $N^{3/2}$ of the quantum Fisher information for frequency estimation with a general initial state of $N$ two-level atoms in the presence of local non-Markovian dephasing noise, which was demonstrated for a GHZ state by A. W. Chin, S. F. Huelga, M. B. Plenio (2012). For collective dephasing we prove that non-Markovian noise allows for better scaling for both correlated and uncorelated states. The quantum enhancement in precision is at least as good as in the local case.

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Katarzyna Macieszczak. 2014-03-06. The Zeno limit in frequency estimation with non-Markovian environments. https://arxiv.org/abs/1403.1333

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