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arXiv · 1407.7681

Comparing different modes of quantum state transfer in a XXZ spin chain

Sima Pouyandeh·Farhad Shahbazi
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Abstract

We study the information transferring ability of a spin-1/2 XXZ Hamiltonian for two different modes of state transfer, namely, the well studied attaching scenario and the recently proposed measurement induced transport. The latter one has been inspired by recent achievements in optical lattice experiments for local addressability of individual atoms and their time evolution when only local rotations and measurements are available and local control of the Hamiltonian is very limited. We show that while measurement induced transport gives higher fidelity for quantum state transfer around the isotropic Heisenberg point, its superiority is less pronounced in non-interacting free fermionic XX phase. Moreover, we study the quality of state transfer in the presence of thermal fluctuations and environmental interactions and show that measurement scheme gives higher fidelity for low temperatures and weak interaction with environment.

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Sima Pouyandeh, Farhad Shahbazi. 2014-08-03. Comparing different modes of quantum state transfer in a XXZ spin chain. https://arxiv.org/abs/1407.7681

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