  We investigate quantum correlations in continuous wave polarization squeezed
laser light generated from one and two optical parametric amplifiers,
respectively. A general expression of how Stokes operator variances decompose
into two mode quadrature operator variances is given. Stokes parameter variance
spectra for four different polarization squeezed states have been measured and
compared with a coherent state. Our measurement results are visualized by
three-dimensional Stokes operator noise volumes mapped on the quantum Poincare
sphere. We quantitatively compare the channel capacity of the different
continuous variable polarization states for communication protocols. It is
shown that squeezed polarization states provide 33% higher channel capacities
than the optimum coherent beam protocol.
