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arXiv · 1201.3576

Quantum state transfer through a spin chain in a multi-excitation subspace

Zhao-Ming Wang·Rui-Song Ma·C. Allen Bishop·Yong-Jian Gu
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Abstract

We investigate the quality of quantum state transfer through a uniformly coupled antiferromagnetic spin chain in a multi-excitation subspace. The fidelity of state transfer using multi-excitation channels is found to compare well with communication protocols based on the ground state of a spin chain with ferromagnetic interactions. Our numerical results support the conjecture that the fidelity of state transfer through a multi-excitation subspace only depends on the number of initial excitations present in the chain and is independent of the excitation ordering. Based on these results, we describe a communication scheme which requires little effort for preparation.

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Zhao-Ming Wang, Rui-Song Ma, C. Allen Bishop, Yong-Jian Gu. 2012-01-17. Quantum state transfer through a spin chain in a multi-excitation subspace. https://doi.org/10.1103/physreva.86.022330

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