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arXiv · 1708.01823

High-fidelity state transfer through long-range correlated disordered quantum channels

Guilherme M. A. Almeida·Francisco A. B. F. de Moura·Marcelo L. Lyra
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Abstract

We study quantum-state transfer in $XX$ spin-$1/2$ chains where both communicating spins are weakly coupled to a channel featuring disordered on-site magnetic fields. Fluctuations are modelled by long-range correlated sequences with self-similar profile obeying a power-law spectrum. We show that the channel is able to perform an almost perfect quantum-state transfer in most of the samples even in the presence of significant amounts of disorder provided the degree of those correlations is strong enough. In that case, we also show that the lack of mirror symmetry does not affect much the likelihood of having high-quality outcomes. Our results advance a further step in designing robust devices for quantum communication protocols.

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Guilherme M. A. Almeida, Francisco A. B. F. de Moura, Marcelo L. Lyra. 2017-08-05. High-fidelity state transfer through long-range correlated disordered quantum channels. https://doi.org/10.1016/j.physleta.2018.03.028

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