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arXiv · 1612.07826

Quantum noise generated by local random Hamiltonians

Marcin Markiewicz·Zbigniew Puchala·Anna de Rosier·Wieslaw Laskowski·Karol Zyczkowski
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Abstract

We investigate the impact of a local random unitary noise on multipartite quantum states of an arbitrary dimension. We follow the dynamical approach, in which the single-particle unitaries are generated by local random Hamiltonians. Assuming short evolution time we derive a lower bound on the fidelity between an initial and the final state transformed by this type of noise. This result is based on averaging the Tamm-Mandelstam bound and holds for a wide class of distributions of random Hamiltonians fulfilling specific symmetry conditions. It is showed how the sensitivity of a given pure quantum state to the discussed type of noise depends on the properties of single-particle and bipartite reduced states.

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Marcin Markiewicz, Zbigniew Puchala, Anna de Rosier, Wieslaw Laskowski, Karol Zyczkowski. 2017-03-15. Quantum noise generated by local random Hamiltonians. https://doi.org/10.1103/physreva.95.032333

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