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arXiv · 2509.19685

Quantum metrology in the presence of correlated noise via Markovian embedding

Arpan Das·Rafał Demkowicz-Dobrzański
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Abstract

We analyze quantum metrological protocols, where the sensing system is linearly coupled to a bosonic environment, by performing a Markovian embedding of the problem based on pseudomode formalism. This allows us to effectively model the problem using low-dimensional environment and apply recently developed powerful tools that yield optimal metrological protocols and fundamental metrological bounds for correlated-noise models. We illustrate the method by investigating a frequency estimation protocol in the presence of noise modeled effectively as a damped Jaynes-Cummings dynamics.

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Arpan Das, Rafał Demkowicz-Dobrzański. 2025-09-24. Quantum metrology in the presence of correlated noise via Markovian embedding. https://doi.org/10.1103/43wz-mtrk

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