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arXiv · 2009.12497

$k$-Uniform states and quantum information masking

Fei Shi·Mao-Sheng Li·Lin Chen·Xiande Zhang
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Abstract

A pure state of $N$ parties with local dimension $d$ is called a $k$-uniform state if all the reductions to $k$ parties are maximally mixed. Based on the connections among $k$-uniform states, orthogonal arrays and linear codes, we give general constructions for $k$-uniform states. We show that when $d\geq 4k-2$ (resp. $d\geq 2k-1$) is a prime power, there exists a $k$-uniform state for any $N\geq 2k$ (resp. $2k\leq N\leq d+1$). Specially, we give the existence of $4,5$-uniform states for almost every $N$-qudits. Further, we generalize the concept of quantum information masking in bipartite systems given by [Modi \emph{et al.} {Phys. Rev. Lett. \textbf{120}, 230501 (2018)}] to $k$-uniform quantum information masking in multipartite systems, and we show that $k$-uniform states and quantum error-correcting codes can be used for $k$-uniform quantum information masking.

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Fei Shi, Mao-Sheng Li, Lin Chen, Xiande Zhang. 2020-09-26. $k$-Uniform states and quantum information masking. https://doi.org/10.1103/physreva.104.032601

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