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arXiv · 1209.2285

Optimal transfer of an unknown state via a bipartite operation

Yang Liu·Yu Guo·D. L. Zhou
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Abstract

A fundamental task in quantum information science is to transfer an unknown state from particle $A$ to particle $B$ (often in remote space locations) by using a bipartite quantum operation $\mathcal{E}^{AB}$. We suggest the power of $\mathcal{E}^{AB}$ for quantum state transfer (QST) to be the maximal average probability of QST over the initial states of particle $B$ and the identifications of the state vectors between $A$ and $B$. We find the QST power of a bipartite quantum operations satisfies four desired properties between two $d$-dimensional Hilbert spaces. When $A$ and $B$ are qubits, the analytical expressions of the QST power is given. In particular, we obtain the exact results of the QST power for a general two-qubit unitary transformation.

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Yang Liu, Yu Guo, D. L. Zhou. 2012-09-11. Optimal transfer of an unknown state via a bipartite operation. https://doi.org/10.1209/0295-5075%2F102%2F50003

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