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arXiv · 1808.04662

Coherence measures based on sandwiched R\'{e}nyi relative entropy

Jianwei Xu
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Abstract

Coherence is a fundamental ingredient for quantum physics and a key resource for quantum information theory. Baumgratz, Cramer, and Plenio established a rigorous framework (BCP framework) for quantifying coherence [T. Baumgratz, M. Cramer, and M. B. Plenio, Phys. Rev. Lett. \textbf{113}, 140401 (2014)]. In this paper, under the BCP framework we provide two classes of coherence measures based on the sandwiched R\'{e}nyi relative entropy. We also prove that we can not get new coherence measures $f(C(\cdot))$ by a function $f$ acting on a given coherence measure $C$, except the case of qubit states.

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Jianwei Xu. 2018-08-14. Coherence measures based on sandwiched R\'{e}nyi relative entropy. https://doi.org/10.1088/1674-1056/ab5930

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