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arXiv · 1611.03035

Enhancing quantum state transfer efficiency in binary-tree spin networks by partially collapsing measurements

Naghi Behzadi·Bahram Ahansaz
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Abstract

In this work, quantum state transfer (QST) over binary-tree spin networks is studied by using advantages of partially collapsing measurements. To this aim, we perform initially a weak measurement (WM) on central qubit of the binary-tree network, which encoding the state of concern and after time evolution of the whole system, a quantum measurement reversal (QMR) on the destined qubit is performed. By taking the optimal value of the QMR, it is shown that the QST can be improved considerably by controlling the WM strength and by choosing it close enough to 1, near-perfect QST can be achieved. We also show that how entanglement distribution quality over the binary-tree spin network can be obviously improved by using this approach.

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Naghi Behzadi, Bahram Ahansaz. 2016-11-16. Enhancing quantum state transfer efficiency in binary-tree spin networks by partially collapsing measurements. https://doi.org/10.1007/s11128-018-1860-7

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