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arXiv · 1301.1774

Quantum-state transfer via resonant tunnelling through local field induced barriers

S. Lorenzo·T. J. G. Apollaro·A. Sindona·F. Plastina
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Abstract

Efficient quantum-state transfer is achieved in a uniformly coupled spin-1/2 chain, with open boundaries, by application of local magnetic fields on the second and last-but-one spins, respectively. These effective \textit{barriers} induce appearance of two eigenstates, bi-localized at the edges of the chain, which allow a high quality transfer also at relatively long distances. The same mechanism may be used to send an entire e-bit (e.g., an entangled qubit pair) from one to the other end of the chain.

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S. Lorenzo, T. J. G. Apollaro, A. Sindona, F. Plastina. 2013-04-25. Quantum-state transfer via resonant tunnelling through local field induced barriers. https://doi.org/10.1103/physreva.87.042313

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