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arXiv · 1808.07180

Quantum metrology out of equilibrium

Sholeh Razavian·Matteo G. A. Paris
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Abstract

We address open quantum systems out-of-equilibrium as effective quantum probes for the characterisation of their environment. We discuss estimation schemes for parameters driving a de-phasing evolution of the probe and then focus on qubits, establishing a relationship between the quantum Fisher information and the residual coherence of the probe. Finally, we apply our results to the characterisation of the ohmicity parameter of a bosonic environment.

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Sholeh Razavian, Matteo G. A. Paris. 2018-08-22. Quantum metrology out of equilibrium. https://doi.org/10.1016/j.physa.2019.03.125

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