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arXiv · 1402.5395

Non-Markovianity through accessible information

F. F. Fanchini·G. Karpat·B. Çakmak·L. K. Castelano·G. H. Aguilar·O. Jiménez Farías·S. P. Walborn·P. H. Souto Ribeiro·M. C. de Oliveira
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Abstract

The degree of non-Markovianity of quantum processes has been characterized in several different ways in the recent literature. However, the relationship between the non-Markovian behavior and the flow of information between the system and the environment through an entropic measure has not been yet established. We propose an entanglement-based measure of non-Markovianity by employing the concept of assisted knowledge, where the environment E, acquires information about a system S, by means of its measurement apparatus A. The assisted knowledge, based on the accessible information in terms of von-Neumann entropy, monotonically increases in time for all Markovian quantum processes. We demonstrate that the signatures of non-Markovianity can be captured by the nonmonotonic behaviour of the assisted knowledge. We explore this scenario for a two-level system undergoing a relaxation process, through an experimental implementation using an optical approach that allows full access to the state of the environment.

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F. F. Fanchini, G. Karpat, B. Çakmak, L. K. Castelano, G. H. Aguilar, O. Jiménez Farías, S. P. Walborn, P. H. Souto Ribeiro, M. C. de Oliveira. 2014-06-04. Non-Markovianity through accessible information. https://doi.org/10.1103/physrevlett.112.210402

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