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arXiv · 2104.12243

Exploiting Gaussian steering to probe non-Markovianity due to the interaction with a structured environment

Massimo Frigerio·Samaneh Hesabi·Davood Afshar·Matteo G. A. Paris
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Abstract

We put forward a measure based on Gaussian steering to quantify the non-Markovianity of continuous-variable (CV) Gaussian quantum channels. We employ the proposed measure to assess and compare the non-Markovianity of a quantum Brownian motion (QBM) channel, originating from the interaction with Ohmic and sub-Ohmic environments with spectral densities described by a Lorentz-Drude cutoff, both at high and low temperatures, showing that sub-Ohmic, high temperature environments lead to highly non-Markovian evolution, with cyclic backflows of Gaussian steerability from the environment to the system. Our results add to the understanding of the interplay between quantum correlations and non-Markovianity for CV systems, and could be implemented at the experimental level to quantify non-Markovianity in some physical scenarios.

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Massimo Frigerio, Samaneh Hesabi, Davood Afshar, Matteo G. A. Paris. 2021-04-25. Exploiting Gaussian steering to probe non-Markovianity due to the interaction with a structured environment. https://doi.org/10.1103/physreva.104.052203

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