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arXiv · 0704.3027

Full control by locally induced relaxation

Daniel Burgarth·Vittorio Giovannetti
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Abstract

We demonstrate a scheme for controlling a large quantum system by acting on a small subsystem only. The local control is mediated to the larger system by some fixed coupling Hamiltonian. The scheme allows to transfer arbitrary and unknown quantum states from a memory on the large system (``upload access'') as well as the inverse (``download access''). We study sufficient conditions of the coupling Hamiltonian and give lower bounds on the fidelities for downloading and uploading.

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Daniel Burgarth, Vittorio Giovannetti. 2007-04-23. Full control by locally induced relaxation. https://doi.org/10.1103/physrevlett.99.100501

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