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Preparation of pure and mixed polarization qubits and the direct measurement of figures of merit

R. B. A. Adamson·L. K. Shalm·A. M. Steinberg
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Abstract

Non-classical joint measurements can hugely improve the efficiency with which certain figures of merit of quantum systems are measured. We use such a measurement to determine a particular figure of merit, the purity, for a polarization qubit. In the process we highlight some of subtleties involved in common methods for generating decoherence in quantum optics.

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R. B. A. Adamson, L. K. Shalm, A. M. Steinberg. 2006-11-20. Preparation of pure and mixed polarization qubits and the direct measurement of figures of merit. https://doi.org/10.1103/physreva.75.012104

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