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arXiv · 0807.2171

Invariant indices of polarimetric purity. Generalized indices of purity for nxn covariance matrices

I. San Jose·J. J. Gil
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Abstract

A proper set of indices characterizing the polarimetric purity of light and material media is defined from the eigenvalues of the corresponding coherency matrix. A simple and generalizable relation of these indices with the current parameters characterizing the global purity is obtained. A general definition for systems characterized by nxn positive semidefinite Hermitian matrices is introduced in terms of the corresponding eigenvalues and diagonal Gell-Mann matrices. The set of n-1 indices of purity has a nested structure and provide complete information about the statistical purity of the system.

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I. San Jose, J. J. Gil. 2008-07-14. Invariant indices of polarimetric purity. Generalized indices of purity for nxn covariance matrices. https://doi.org/10.1016/j.optcom.2010.08.077

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