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Quantum measurement of a mesoscopic spin ensemble

G. Giedke·J. M. Taylor·D. D'Alessandro·M. D. Lukin·A. Imamoglu
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Abstract

We describe a method for precise estimation of the polarization of a mesoscopic spin ensemble by using its coupling to a single two-level system. Our approach requires a minimal number of measurements on the two-level system for a given measurement precision. We consider the application of this method to the case of nuclear spin ensemble defined by a single electron-charged quantum dot: we show that decreasing the electron spin dephasing due to nuclei and increasing the fidelity of nuclear-spin-based quantum memory could be within the reach of present day experiments.

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G. Giedke, J. M. Taylor, D. D'Alessandro, M. D. Lukin, A. Imamoglu. 2006-09-18. Quantum measurement of a mesoscopic spin ensemble. https://doi.org/10.1103/physreva.74.032316

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