2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/228257Theoretical analysis is presented on quantum state evolution of polarization light waves at frequencies $ω_{o}$ and $ω_{e}$ in a periodically poled nonlinear crystal (PPNC). It is shown that the variances of all the four Stokes parameters can be squeezed.9 pages, 5 figuresQuantum Physicstext