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arXiv · 0905.3373

Scalable quantum computation via local control of only two qubits

Daniel Burgarth·Koji Maruyama·Michael Murphy·Simone Montangero·Tommaso Calarco·Franco Nori·Martin B. Plenio
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Abstract

We apply quantum control techniques to control a large spin chain by only acting on two qubits at one of its ends, thereby implementing universal quantum computation by a combination of quantum gates on the latter and swap operations across the chain. It is shown that the control sequences can be computed and implemented efficiently. We discuss the application of these ideas to physical systems such as superconducting qubits in which full control of long chains is challenging.

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Daniel Burgarth, Koji Maruyama, Michael Murphy, Simone Montangero, Tommaso Calarco, Franco Nori, Martin B. Plenio. 2009-06-29. Scalable quantum computation via local control of only two qubits. https://doi.org/10.1103/physreva.81.040303

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