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arXiv · 0805.3637

Optimal state for keeping reference frames aligned and the Platonic solids

Piotr Kolenderski·Rafal Demkowicz-Dobrzanski
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Abstract

The optimal N qubit states featuring highest sensitivity to small misalignment of cartesian reference frames are found using the Quantum Cramer-Rao bound. It is shown that the optimal states are supported on the symmetric subspace and hence are mathematically equivalent to a single spin J=N/2. Majorana representation of spin states is used to reveal a beautiful connection between the states optimal for aligning reference frames and the platonic solids.

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Piotr Kolenderski, Rafal Demkowicz-Dobrzanski. 2008-12-01. Optimal state for keeping reference frames aligned and the Platonic solids. https://doi.org/10.1103/physreva.78.052333

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