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arXiv · 1203.5516

99%-fidelity ballistic quantum-state transfer through long uniform channels

T. J. G. Apollaro·L. Banchi·A. Cuccoli·R. Vaia·P. Verrucchi
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Abstract

Quantum-state transfer with fidelity higher than 0.99 can be achieved in the ballistic regime of an arbitrarily long one-dimensional chain with uniform nearest-neighbor interaction, except for the two pairs of mirror symmetric extremal bonds, say x (first and last) and y (second and last-but-one). These have to be roughly tuned to suitable values x ~ 2 N^{-1/3} and y ~ 2^{3/4} N^{-1/6}, N being the chain length. The general framework can describe the end-to-end response in different models, such as fermion or boson hopping models and XX spin chains.

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T. J. G. Apollaro, L. Banchi, A. Cuccoli, R. Vaia, P. Verrucchi. 2012-03-25. 99%-fidelity ballistic quantum-state transfer through long uniform channels. https://doi.org/10.1103/physreva.85.052319

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