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arXiv · 1906.01311

$k$-uniform mixed states

Waldemar Klobus·Adam Burchardt·Adrian Kolodziejski·Mahasweta Pandit·Tamas Vertesi·Karol Zyczkowski·Wieslaw Laskowski
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Abstract

We investigate the maximum purity that can be achieved by k-uniform mixed states of N parties. Such N-party states have the property that all their k-party reduced states are maximally mixed. A scheme to construct explicitly k-uniform states using a set of specific N-qubit Pauli matrices is proposed. We provide several different examples of such states and demonstrate that in some cases the state corresponds to a particular orthogonal array. The obtained states, despite being mixed, reveal strong non-classical properties such as genuine multipartite entanglement or violation of Bell inequalities.

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Waldemar Klobus, Adam Burchardt, Adrian Kolodziejski, Mahasweta Pandit, Tamas Vertesi, Karol Zyczkowski, Wieslaw Laskowski. 2019-09-16. $k$-uniform mixed states. https://doi.org/10.1103/physreva.100.032112

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