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arXiv · 1112.3814

Efficient quantification of non-Gaussian spin distributions

B. Dubost·M. Koschorreck·M. Napolitano·N. Behbood·R. J. Sewell·M. W. Mitchell
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Abstract

We study theoretically and experimentally the quantification of non-Gaussian distributions via non-destructive measurements. Using the theory of cumulants, their unbiased estimators, and the uncertainties of these estimators, we describe a quantification which is simultaneously efficient, unbiased by measurement noise, and suitable for hypothesis tests, e.g., to detect non-classical states. The theory is applied to cold $^{87}$Rb spin ensembles prepared in non-gaussian states by optical pumping and measured by non-destructive Faraday rotation probing. We find an optimal use of measurement resources under realistic conditions, e.g., in atomic ensemble quantum memories.

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B. Dubost, M. Koschorreck, M. Napolitano, N. Behbood, R. J. Sewell, M. W. Mitchell. 2011-12-16. Efficient quantification of non-Gaussian spin distributions. https://doi.org/10.1103/physrevlett.108.183602

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