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arXiv · 1809.09372

Disorder-safe entanglement transfer through ladder qubit chains

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

We study an entanglement transfer protocol in a two-leg ladder spin-1/2 chain in the presence of disorder. In the regime where on-site energies and the intrachain couplings follow aproximately constant proportions locally, we set up a scheme for high-fidelity state transfer via a disorder-protected subspace wherein fluctuations in the parameters do not depend on the global disorder of the system, accounted by $W$. Moreover, we find that the leakage of information from that subspace is actually suppressed upon increasing $W$ and thus the transfer fidelity, evaluated through the entanglement concurrence at the other end of the chain, builds up with the disorder strength.

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Guilherme M. A. Almeida, Andre M. C. Souza, Francisco, A. B. F. de Moura, Marcelo, L. Lyra. 2018-09-25. Disorder-safe entanglement transfer through ladder qubit chains. https://doi.org/10.1016/j.physleta.2019.125847

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