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arXiv · 1207.1298

Witnessed entanglement and the geometric measure of quantum discord

Tiago Debarba·Thiago O. Maciel·Reinaldo O. Vianna
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Abstract

We establish relations between geometric quantum discord and entanglement quantifiers obtained by means of optimal witness operators. In particular, we prove a relation between negativity and geometric discord in the Hilbert-Schmidt norm, which is slightly different from a previous conjectured one [Phys. Rev. A 84, 052110 (2011)].We also show that, redefining the geometric discord with the trace norm, better bounds can be obtained. We illustrate our results numerically.

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Tiago Debarba, Thiago O. Maciel, Reinaldo O. Vianna. 2012-07-05. Witnessed entanglement and the geometric measure of quantum discord. https://doi.org/10.1103/physreva.86.024302

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