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arXiv · 0910.1459

Fidelity threshold for long-range entanglement in quantum networks

S. Perseguers
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Abstract

We present a strategy to generate long-range entanglement in noisy quantum networks. We consider a cubic lattice whose bonds are partially entangled mixed states of two qubits, and where quantum operations can be applied perfectly at the nodes. In contrast to protocols designed for one- or two-dimensional regular lattices, we find that entanglement can be created between arbitrarily distant qubits if the fidelity of the bonds is higher than a critical value, independent of the system size. Therefore, we show that a constant overhead of local resources, together with connections of finite fidelity, is sufficient to achieve long-distance quantum communication in noisy networks.

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S. Perseguers. 2010-01-18. Fidelity threshold for long-range entanglement in quantum networks. https://doi.org/10.1103/physreva.81.012310

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