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Maximally polarized states for quantum light fields

L. L. Sanchez-Soto·E. C. Yustas·G. Bjork·A. B. Klimov
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Abstract

The degree of polarization of a quantum state can be defined as its Hilbert-Schmidt distance to the set of unpolarized states. We demonstrate that the states optimizing this degree for a fixed average number of photons $\bar{N}$ present a fairly symmetric, parabolic photon statistics, with a variance scaling as $\bar{N}^2$. Although no standard optical process yields such a statistics, we show that, to an excellent approximation, a highly squeezed vacuum can be considered as maximally polarized.

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L. L. Sanchez-Soto, E. C. Yustas, G. Bjork, A. B. Klimov. 2006-10-05. Maximally polarized states for quantum light fields. https://doi.org/10.1103/physreva.76.043820

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