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arXiv · 1605.09783

Quantifying entanglement of maximal dimension in bipartite mixed states

Gael Sentís·Christopher Eltschka·Otfried Gühne·Marcus Huber·Jens Siewert
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Abstract

The Schmidt coefficients capture all entanglement properties of a pure bipartite state and therefore determine its usefulness for quantum information processing. While the quantification of the corresponding properties in mixed states is important both from a theoretical and a practical point of view, it is considerably more difficult, and methods beyond estimates for the concurrence are elusive. In particular this holds for a quantitative assessment of the most valuable resource, the maximum possible Schmidt number of an arbitrary mixed state. We derive a framework for lower bounding the appropriate measure of entanglement, the so-called G-concurrence, through few local measurements. Moreover, we show that these bounds have relevant applications also for multipartite states.

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Gael Sentís, Christopher Eltschka, Otfried Gühne, Marcus Huber, Jens Siewert. 2019-04-05. Quantifying entanglement of maximal dimension in bipartite mixed states. https://doi.org/10.1103/physrevlett.117.190502

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