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arXiv · 1010.1920

Tight lower bound to the geometric measure of quantum discord

Ali Saif M. Hassan·Behzad Lari·Pramod S. Joag
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Abstract

Dakic, Vedral and Brukner [Physical Review Letters \tf{105},190502 (2010)] gave a geometric measure of quantum discord in a bipartite quantum state as the distance of the state from the closest classical quantum (or zero discord) state and derived an explicit formula for a two qubit state. Further, S.Luo and S.Fu [Physical Review A \tf{82}, 034302 (2010)] obtained a generic form of this geometric measure for a general bipartite state and established a lower bound. In this brief report we obtain a rigorous lower bound to the geometric measure of quantum discord in a general bipartite state which dominates that obtained by S.Luo and S.Fu.

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Ali Saif M. Hassan, Behzad Lari, Pramod S. Joag. 2012-01-30. Tight lower bound to the geometric measure of quantum discord. https://doi.org/10.1103/physreva.85.024302

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