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arXiv · 2001.01738

Detection of quantum non-Markovianity close to the Born-Markov approximation

Thais de Lima Silva·Stephen P. Walborn·Marcelo F. Santos·Gabriel H. Aguilar·Adrián A. Budini
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Abstract

We calculate in an exact way the conditional past-future correlation for the decay dynamics of a two-level system in a bosonic bath. Different measurement processes are considered. In contrast to quantum memory measures based solely on system propagator properties, here memory effects are related to a convolution structure involving two system propagators and the environment correlation. This structure allows to detect memory effects even close to the validity of the Born-Markov approximation. An alternative operational-based definition of environment-to-system backflow of information follows from this result. We provide experimental support to our results by implementing the dynamics and measurements in a photonic experiment.

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Thais de Lima Silva, Stephen P. Walborn, Marcelo F. Santos, Gabriel H. Aguilar, Adrián A. Budini. 2020-01-06. Detection of quantum non-Markovianity close to the Born-Markov approximation. https://doi.org/10.1103/physreva.101.042120

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