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arXiv · 1706.08742

Conditional quantum entropy power inequality for $d$-level quantum systems

Kabgyun Jeong·Soojoon Lee·Hyunseok Jeong
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Abstract

We propose an extension of the quantum entropy power inequality for finite dimensional quantum systems, and prove a conditional quantum entropy power inequality by using the majorization relation as well as the concavity of entropic functions also given by Audenaert, Datta, and Ozols [J. Math. Phys. 57, 052202 (2016)]. Here, we make particular use of the fact that a specific local measurement after a partial swap operation (or partial swap quantum channel) acting only on finite dimensional bipartite subsystems does not affect the majorization relation for the conditional output states when a separable ancillary subsystem is involved. We expect our conditional quantum entropy power inequality to be useful, and applicable in bounding and analyzing several capacity problems for quantum channels.

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Kabgyun Jeong, Soojoon Lee, Hyunseok Jeong. 2017-06-27. Conditional quantum entropy power inequality for $d$-level quantum systems. https://doi.org/10.1088/1751-8121%2Faab037

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