STABILITY OF THE STATE OF ELLIPTIC POLARI ZATION WITH A PICOSECOND LASER-PULSE

Using a single intense picosecond laser pulse (YAG lambda=532nm) we re port the experimental measurements of intensity induced changes of opt ical polarization (ellipse rotation) in a homogeneous, isotropic, ense mble of molecules having anisotropic polarisability tensors, for which we obtain nonlinear susceptibilities chi(xyyx), chi(xxxx) and the Ker r coefficient n(2). These values obtained for different length carbond isulfide cells are compared with other results of various authors. We have also studied the transmitted ligth intensity, as well as the spat ial profile in the transverse direction of the outgoing pulse. We demo nstrate at low intensities the existence of a change in the ellipticit y and ellipse rotation without absorption, and saturation behavior due to self-focusing and stimulated Rayleigh scattering at high intensiti es.