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Enhancement of entanglement transfer in a spin chain by phase shift-control

K. Maruyama·T. Iitaka·F. Nori
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Abstract

We study the effect of a phase shift on the amount of transferrable two-spin entanglement in a spin chain. We consider a ferromagnetic Heisenberg/XY spin chain, both numerically and analytically, and two mechanisms to generate a phase shift, the Aharonov-Casher effect and the Dzyaloshinskii-Moriya interaction. In both cases, the maximum attainable entanglement is shown to be significantly enhanced, suggesting its potential usefulness in quantum information processing.

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K. Maruyama, T. Iitaka, F. Nori. 2007-01-24. Enhancement of entanglement transfer in a spin chain by phase shift-control. https://doi.org/10.1103/physreva.75.012325

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