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arXiv · 1301.6015

On the complexity of controlling quantum many-body dynamics

T. Caneva·A. Silva·R. Fazio·S. Lloyd·T. Calarco·S. Montangero
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Abstract

We demonstrate that arbitrary time evolutions of many-body quantum systems can be reversed even in cases when only part of the Hamiltonian can be controlled. The reversed dynamics obtained via optimal control --contrary to standard time-reversal procedures-- is extremely robust to external sources of noise. We provide a lower bound on the control complexity of a many-body quantum dynamics in terms of the dimension of the manifold supporting it, elucidating the role played by integrability in this context.

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T. Caneva, A. Silva, R. Fazio, S. Lloyd, T. Calarco, S. Montangero. 2014-05-05. On the complexity of controlling quantum many-body dynamics. https://doi.org/10.1103/physreva.89.042322

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