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Quantum state swapping via qubit network with Hubbard interaction

S. Yang·Z. Song·C. P. Sun
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Abstract

We study the quantum state transfer (QST) in a class of qubit network with on-site interaction, which is described by the generalized Hubbard model with engineered couplings. It is proved that the system of two electrons with opposite spins in this quantum network of $N$ sites can be rigorously reduced into $N$ one dimensional engineered single Bloch electron models with central potential barrier. With this observation we find that such system can perform a perfect QST, the quantum swapping between two distant electrons with opposite spins. Numerical results show such QST and the resonant-tunnelling for the optimal on-site interaction strengths.

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S. Yang, Z. Song, C. P. Sun. 2005-10-14. Quantum state swapping via qubit network with Hubbard interaction. https://doi.org/10.1103/physrevb.73.195122

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