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arXiv · 1503.04550

High-dimensional quantum state transfer in a noisy network environment

Wei Qin·Jun-Lin Li·Gui-Lu Long
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Abstract

We propose and analyze an efficient high-dimensional quantum state transfer protocol in an XX coupling spin network with a hypercube structure or chain structure. Under free spin wave approximation, unitary evolution results in a perfect high-dimensional quantum swap operation requiring neither external manipulation nor weak coupling. Evolution time is independent of either distance between registers or dimensions of sent states, which can enable improvements in computational efficiency. In the low temperature regime and thermodynamic limit, the decoherence by noisy environment is studied with a model of an antiferromagnetic spin bath coupled to quantum channels via an Ising type interaction is studied. it is found that while the decoherence reduces the fidelity of state transfer, increasing intra-channel coupling can strongly suppress such effects. These observations demonstrate that robustness of the proposed scheme.

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Wei Qin, Jun-Lin Li, Gui-Lu Long. 2015-03-16. High-dimensional quantum state transfer in a noisy network environment. https://doi.org/10.1088/1674-1056/24/4/040305

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