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On Weyl-covariant channels

M. Fukuda·A. S. Holevo
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Abstract

Formalism of discrete noncommutative Fourier transform is developed and applied to the study of Weyl-covariant channels. We then extend a result in quant-ph/0509126 concerning a bound of the maximal output 2-norm of a Weyl-covariant channel. A class of channels which attain the bound is introduced, for which the multiplicativity of the maximal output 2-norm is proven. Complementary channels are described which share the multiplicativity properties with the Weyl-covariant channels.

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M. Fukuda, A. S. Holevo. 2006-11-15. On Weyl-covariant channels. https://arxiv.org/abs/quant-ph/0510148

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