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arXiv · 1807.07827

Preservation of quantum non-bilocal correlations in noisy entanglement-swapping experiments using weak measurements

Shashank Gupta·Shounak Datta·A. S. Majumdar
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Abstract

A tripartite quantum network is said to be bilocal if two independent sources produce a pair of bipartite entangled states. Quantum non-bilocal correlation emerges when the central party which possesses two particles from two different sources performs Bell-state measurement on them and nonlocality is generated between the other two uncorrelated systems in this entanglement-swapping protocol. The interaction of such systems with the environment reduces quantum non-bilocal correlations. Here we show that the diminishing effect modelled by the amplitude damping channel can be slowed down by employing the technique of weak measurements and reversals. It is demonstrated that for a large range of parameters the quantum non-bilocal correlations are preserved against decoherence by taking into account the average success rate of the post-selection governing weak measurements.

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Shashank Gupta, Shounak Datta, A. S. Majumdar. 2018-07-20. Preservation of quantum non-bilocal correlations in noisy entanglement-swapping experiments using weak measurements. https://doi.org/10.1103/physreva.98.042322

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