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arXiv · 1503.00836

Quantifying Non-Markovianity with Temporal Steering

Shin-Liang Chen·Neill Lambert·Che-Ming Li·Adam Miranowicz·Yueh-Nan Chen·Franco Nori
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Abstract

Einstein-Podolsky-Rosen (EPR) steering is a type of quantum correlation which allows one to remotely prepare, or steer, the state of a distant quantum system. While EPR steering can be thought of as a purely spatial correlation there does exist a temporal analogue, in the form of single-system temporal steering. However, a precise quantification of such temporal steering has been lacking. Here we show that it can be measured, via semidefinite programming, with a temporal steerable weight, in direct analogy to the recently proposed EPR steerable weight. We find a useful property of the temporal steerable weight in that it is a non-increasing function under completely-positive trace-preserving maps and can be used to define a sufficient and practical measure of strong non-Markovianity.

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Shin-Liang Chen, Neill Lambert, Che-Ming Li, Adam Miranowicz, Yueh-Nan Chen, Franco Nori. 2016-07-22. Quantifying Non-Markovianity with Temporal Steering. https://doi.org/10.1103/physrevlett.116.020503

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