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arXiv · 1806.00653

Some notes on the robustness of k-coherence and k-entanglement

Nathaniel Johnston·Chi-Kwong Li·Sarah Plosker·Yiu-Tung Poon·Bartosz Regula
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Abstract

We show that two related measures of k-coherence, called the standard and generalized robustness of k-coherence, are equal to each other when restricted to pure states. As a direct application of the result, we establish an equivalence between two analogous measures of Schmidt rank k-entanglement for all pure states. This answers conjectures raised in the literature regarding the evaluation of the quantifiers, and facilitates an efficient quantification of pure-state resources by introducing computable closed-form expressions for the two measures.

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Nathaniel Johnston, Chi-Kwong Li, Sarah Plosker, Yiu-Tung Poon, Bartosz Regula. 2018-06-02. Some notes on the robustness of k-coherence and k-entanglement. https://doi.org/10.1103/physreva.98.022328

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