Upper Bound on Singlet Fraction of Two Qubit Mixed Entangled States

Satyabrata Adhikari; Atul Kumar

doi:10.1007/s11128-016-1295-y

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arXiv · 1403.6929

Upper Bound on Singlet Fraction of Two Qubit Mixed Entangled States

Satyabrata Adhikari·Atul Kumar

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Abstract

We demonstrate the possibility of achieving the maximum possible singlet fraction using a entangled mixed two-qubit state as a resource. For this, we establish a tight upper bound on singlet fraction and show that the maximal singlet fraction obtained in \cite{Verstraete} does not attain the obtained upper bound on the singlet fraction. Interestingly, we found that the required upper bound can in fact be achieved using local filtering operations.

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Satyabrata Adhikari, Atul Kumar. 2014-03-28. Upper Bound on Singlet Fraction of Two Qubit Mixed Entangled States. https://doi.org/10.1007/s11128-016-1295-y

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