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arXiv · 2010.11707

Quantifying quantum coherence based on the Tsallis relative operator entropy

Meng-Li Guo·Zhi-Xiang Jin·Bo Li·Bin Hu·Shao-Ming Fei
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Abstract

Coherence is a fundamental ingredient in quantum physics and a key resource in quantum information processing. The quantification of quantum coherence is of great importance. We present a family of coherence quantifiers based on the Tsallis relative operator entropy. Shannon inequality and its reverse one in Hilbert space operators derived by Furuta [Linear Algebra Appl. 381 (2004) 219] are extended in terms of the parameter of the Tsallis relative operator entropy. These quantifiers are shown to satisfy all the standard criteria for a well-defined measure of coherence and include some existing coherence measures as special cases. Detailed examples are given to show the relations among the measures of quantum coherence.

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Meng-Li Guo, Zhi-Xiang Jin, Bo Li, Bin Hu, Shao-Ming Fei. 2020-10-22. Quantifying quantum coherence based on the Tsallis relative operator entropy. https://doi.org/10.1007/s11128-020-02885-1

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