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arXiv · 2403.04854

Quantum metrology using quantum combs and tensor network formalism

Stanislaw Kurdzialek·Piotr Dulian·Joanna Majsak·Sagnik Chakraborty·Rafal Demkowicz-Dobrzanski
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Abstract

We develop an efficient algorithm for determining optimal adaptive quantum estimation protocols with arbitrary quantum control operations between subsequent uses of a probed channel. We introduce a tensor network representation of an estimation strategy, which drastically reduces the time and memory consumption of the algorithm, and allows us to analyze metrological protocols involving up to $N=50$ qubit channel uses, whereas the state-of-the-art approaches are limited to $N<5$. The method is applied to study the performance of the optimal adaptive metrological protocols in presence of various noise types, including correlated noise.

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Stanislaw Kurdzialek, Piotr Dulian, Joanna Majsak, Sagnik Chakraborty, Rafal Demkowicz-Dobrzanski. 2024-03-07. Quantum metrology using quantum combs and tensor network formalism. https://doi.org/10.1088/1367-2630/ada8d1

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