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Quantum versus classical polarization states: when multipoles count

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 نشر من قبل Luis L. Sanchez. Soto
 تاريخ النشر 2013
  مجال البحث فيزياء
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We advocate for a simple multipole expansion of the polarization density matrix. The resulting multipoles are used to construct bona fide quasiprobability distributions that appear as a sum of successive moments of the Stokes variables; the first one corresponding to the classical picture on the Poincare sphere. We employ the particular case of the $Q$ function to formulate a whole hierarchy of measures that properly assess higher-order polarization correlations.



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