Degeneracy of the polarization ellipse of a light wave in media with a transient nonlinear response of the Kerr type

An analysis is made of the self-induced change in the elliptical polarization of a light wave propagating in an initially isotropic liquid consisting of anisotropic molecules. It is shown that for optical pulses of duration shorter than the relaxation time of the anisotropy, self-precession of the ellipse is accompanied by degeneracy, i.e., the wave becomes linearly polarized.