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arXiv · 2306.01077

Optimal distributed multiparameter estimation in noisy environments

Arne Hamann·Pavel Sekatski·Wolfgang Dür
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Abstract

We consider the task of multiple parameter estimation in the presence of strong correlated noise with a network of distributed sensors. We study how to find and improve noise-insensitive strategies. We show that sequentially probing GHZ states is optimal up to a factor of at most 4. This allows us to connect the problem to single parameter estimation, and to use techniques such as protection against correlated noise in a decoherence-free subspace, or read-out by local measurements.

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Arne Hamann, Pavel Sekatski, Wolfgang Dür. 2023-06-01. Optimal distributed multiparameter estimation in noisy environments. https://doi.org/10.1088/2058-9565%2Fad37d5

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