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arXiv · 2506.10796

Quantifying coherence of quantum channels based on the generalized $\alpha$-$z$-relative R\'{e}nyi entropy

Jiaorui Fan·Zhaoqi Wu·Shao-Ming Fei
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Abstract

By using the Choi-Jamio{\l}kowski isomorphism, we propose a well-defined coherence measure of quantum channels based on the generalized $\alpha$-$z$-relative R\'{e}nyi entropy. In addition, we present an alternative coherence measure of quantum channels by quantifying the commutativity between the channels and the completely dephasing channels with the generalized $\alpha$-$z$-relative R\'{e}nyi entropy. Some elegant properties of the measures are illustrated in detail. Explicit formulas of these coherence measures are derived for some detailed typical quantum channels.

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Jiaorui Fan, Zhaoqi Wu, Shao-Ming Fei. 2025-06-12. Quantifying coherence of quantum channels based on the generalized $\alpha$-$z$-relative R\'{e}nyi entropy. https://doi.org/10.1007/s11128-024-04309-w

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