Polarization dynamics of the fundamental vector soliton of isotropic Kerr media

We characterize fully the polarization dynamics of the fundamental vector soliton of isotropic Kerr materials by measuring the Stokes parameters of an elliptically polarized self-trapped optical beam propagating in a slab planar waveguide. Our experiment clearly shows that this two-component spatial vector soliton exhibits both the so-called ellipse rotation and curved-shape ellipticity that are due to the self-induced nonlinear birefringence between the two components of the vector soliton. The polarization of the vector soliton is accurately determined both in the transverse and longitudinal directions and comparisons with numerical simulations based on two coupled nonlinear Schrödinger equations provide an excellent quantitative agreement. Spatiotemporal numerical simulations that take into account the finite pulse duration of the experimental input optical beam must, however, be used to match rigorously the measured state of polarization of the vector soliton.