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arXiv · 2607.11793

Private Capacity of Quantum Channels Induced by Non-stabilizer Environmental States

Chunhe Xiong·Sunho Kim·Long Long·Junde Wu
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Abstract

We investigate the private capacity of quantum channels using the recently proposed quantum convolution theory for discrete-variable quantum systems. We focus on the role of the magic resource played in this framework. Firstly, for a large class of convolutional channels, we find that the private capacity is zero if the fixed environmental state is a stabilizer state. Moreover, we show that the private capacity can be nonzero for some magic environmental states. Furthermore, we show that the private capacity of a discrete beam splitter unitary is upper-bounded by the amount of magic of the environmental state. In addition, if the environmental state exhibits a certain symmetric structure, even if it is magic, the corresponding private capacity will also vanish for a class of convolution. These results emphasize the role of magic resources in quantum communication

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Chunhe Xiong, Sunho Kim, Long Long, Junde Wu. 2026-07-13. Private Capacity of Quantum Channels Induced by Non-stabilizer Environmental States. https://arxiv.org/abs/2607.11793

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