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arXiv · 2306.08500

Non-equilibrium quantum probing through linear response

Sherry Blair·Giorgio Zicari·Alessio Belenchia·Alessandro Ferraro·Mauro Paternostro
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Abstract

The formalism of linear response theory can be extended to encompass physical situations where an open quantum system evolves towards a non-equilibrium steady-state. Here, we use the framework put forward by Konopik and Lutz [Phys. Rev. Research {\bf 1}, 033156 (2019)] to go beyond unitary perturbations of the dynamics. Considering an open system comprised of two coupled quantum harmonic oscillators, we study the system's response to unitary perturbations, affecting the Hamiltonian dynamics, as well as non-unitary perturbations, affecting the properties of the environment, e.g., its temperature and squeezing. We show that linear response, combined with a quantum probing approach, can effectively provide valuable quantitative information about the perturbation and characteristics of the environment, even in cases of non-unitary dynamics.

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Sherry Blair, Giorgio Zicari, Alessio Belenchia, Alessandro Ferraro, Mauro Paternostro. 2023-06-14. Non-equilibrium quantum probing through linear response. https://doi.org/10.1103/physrevresearch.6.013152

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