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arXiv · 2212.10664

Entangled state distillation from single copy mixed states beyond LOCC

Indranil Biswas·Atanu Bhunia·Indrani Chattopadhyay·Debasis Sarkar
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Abstract

No pure entangled state can be distilled from a $2\otimes 2$ or $2\otimes 3$ mixed state by separable operations. In $3\otimes 3$, pure entanglement can be distilled by separable operation but not by LOCC. In this letter, we proved the conjecture [PRL. 103, 110502 (2009)] that it is possible to distill pure entanglement for $2\otimes 4$ system by LOCC and further improve these in higher dimensions to distill a pure entangled state of Schmidt rank $d$ from a $m\otimes n$ mixed state by separable operation when $m+n \geqslant 3d$. We found results for tripartite systems with target state $d$-level GHZ-type state. These results provide a class of systems where separable operation is strictly stronger than LOCC.

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Indranil Biswas, Atanu Bhunia, Indrani Chattopadhyay, Debasis Sarkar. 2022-12-20. Entangled state distillation from single copy mixed states beyond LOCC. https://doi.org/10.1016/j.physleta.2022.128610

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