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Symmetry

SU(2)-Covariant Quantum Channels

Łukasz Rudnicki, A. B. Klimov, Ariana S. Muñoz, Gerd Leuchs, Luis Lorenzo Sánchez-Soto

Published Jul 5, 2026• 0 citations
Publisher

Abstract

We present a complete characterization of quantum channels covariant under the action of SU(2), a symmetry that arises naturally across a wide range of physical settings. By exploiting the constraints imposed by rotational symmetry, we derive the spectral decomposition of the associated Choi–Jamiołkowski operators and obtain explicit closed-form expressions for the corresponding Kraus operators. This unified framework provides a systematic approach to analyzing the structure and dynamics of SU(2)-covariant noise, with direct applications to quantum communication, information processing, and symmetry-constrained quantum protocols.

DOI
10.3390/sym18071146

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