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arXiv · 0709.0142

Quantum Reference Frames and the Classification of Rotationally-Invariant Maps

J. -C. Boileau·L. Sheridan·M. Laforest·S. D. Bartlett
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Abstract

We give a convenient representation for any map that is covariant with respect to an irreducible representation of SU(2), and use this representation to analyze the evolution of a quantum directional reference frame when it is exploited as a resource for performing quantum operations. We introduce the moments of a quantum reference frame, which serve as a complete description of its properties as a frame, and investigate how many times a quantum directional reference frame represented by a spin-j system can be used to perform a certain quantum operation with a given probability of success. We provide a considerable generalization of previous results on the degradation of a reference frame, from which follows a classification of the dynamics of spin-j system under the repeated action of any covariant map with respect to SU(2).

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J. -C. Boileau, L. Sheridan, M. Laforest, S. D. Bartlett. 2008-03-07. Quantum Reference Frames and the Classification of Rotationally-Invariant Maps. https://doi.org/10.1063/1.2884583

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