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arXiv · 2511.05003

Several kinds of Gaussian quantum channels related to Einstein-Podolsky-Rosen steering

Ruifen Ma·Yanjing Sun·Xiaofei Qi
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Abstract

Quantum steering is a crucial quantum resource that lies intermediate between entanglement and Bell nonlocality. Gaussian channels, meanwhile, play a foundational role in diverse quantum protocols, secure communication, and related fields. In this paper, we focus on several classes of Gaussian channels associated with quantum steering: Gaussian steering-annihilating channels, Gaussian steering-breaking channels, Gaussian unsteerable channels, and maximal Gaussian unsteerable channels. We give the concepts of these channels, derive the necessary and sufficient conditions for a Gaussian channel to belong to each class, and explore the intrinsic relationships among them. Additionally, since quantifying the steering capability of Gaussian channels in continuous-variable systems requires an understanding of the structure of free superchannels, we also provide a detailed characterization of Gaussian unsteerable superchannels and maximal Gaussian unsteerable superchannels.

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Ruifen Ma, Yanjing Sun, Xiaofei Qi. 2026-04-10. Several kinds of Gaussian quantum channels related to Einstein-Podolsky-Rosen steering. https://arxiv.org/abs/2511.05003

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