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Entanglement assisted alignment of reference frames using a dense covariant coding

E. Bagan·M. Baig·R. Munoz-Tapia
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Abstract

We present a procedure inspired by dense coding, which enables a highly efficient transmission of information of a continuous nature. The procedure requires the sender and the recipient to share a maximally entangled state. We deal with the concrete problem of aligning reference frames or trihedra by means of a quantum system. We find the optimal covariant measurement and compute the corresponding average error, which has a remarkably simple close form. The connection of this procedure with that of estimating unitary transformations on qubits is briefly discussed.

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E. Bagan, M. Baig, R. Munoz-Tapia. 2004-04-28. Entanglement assisted alignment of reference frames using a dense covariant coding. https://doi.org/10.1103/physreva.69.050303

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