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Mixed state sensitivity of several quantum information benchmarks

Nicholas A. Peters·Tzu-Chieh Wei·Paul G. Kwiat
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Abstract

We investigate an imbalance between the sensitivity of the common state measures--fidelity, trace distance, concurrence, tangle, von Neumann entropy and linear entropy--when acted on by a depolarizing channel. Further, in this context we explore two classes of two-qubit entangled mixed states. Specifically, we illustrate a sensitivity imbalance between three of these measures for depolarized (i.e., Werner-state like) nonmaximally entangled and maximally entangled mixed states, noting that the size of the imbalance depends on the state's tangle and linear entropy.

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Nicholas A. Peters, Tzu-Chieh Wei, Paul G. Kwiat. 2004-10-22. Mixed state sensitivity of several quantum information benchmarks. https://doi.org/10.1103/physreva.70.052309

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