Anisotropy in the complex refractive index and the third-order nonlinear optical susceptibility of a stretch-oriented film of poly(p-phenylene vinylene)

Birefringence, dichroism, and dispersion of the refractive indices of a free-standing film of poly(p-phenylene vinylene) (PPV) were measured by several techniques. The results are applied to an analysis of anisotropy of the third-order nonlinear optical susceptibility of this material. The anisotropy of both the linear and nonlinear susceptibilities is accounted for by the one-dimensional character of the lowest-energy electronic transition in PPV.