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arXiv · 0705.1560

Spin Star as Switch for Quantum Networks

Man-Hong Yung
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Abstract

Quantum state transfer is an important task in quantum information processing. It is known that one can engineer the couplings of a one-dimensional spin chain to achieve the goal of perfect state transfer. To leverage the value of these spin chains, a spin star is potentially useful for connecting different parts of a quantum network. In this work, we extend the spin-chain engineering problem to the problems with a topology of a star network. We show that a permanently coupled spin star can function as a network switch for transferring quantum states selectively from one node to another by varying the local potentials only. Together with one-dimensional chains, this result allows applications of quantum state transfer be applied to more general quantum networks.

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Man-Hong Yung. 2007-05-10. Spin Star as Switch for Quantum Networks. https://doi.org/10.1088/0953-4075/44/13/135504

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