Anisotropy and dispersion of a Pockels tensor: a benchmark for electro-optic organic thin-film assessment

Abstract

The dominant components of the χ(2)(-ω; ω, 0) nonlinear quadratic susceptibility tensor of a poled polymer-based nonlinear organic thin film are measured independently with a Fabry–Pérot interferometric technique. Electro-optic dispersion is obtained from visible wavelengths up to 1.550 μm leading to a wavelength-independent χ333(2)/χ113(2) nonlinear anisotropy ratio close to 5 for the poly(methyl methacrylate) (PMMA) Disperse Red 1 (DR1) copolymer and close to 3 for the PMMA DR1 guest–host blend. Interaction of the chromophores with their environment is pointed out to be at the origin of these anisotropy ratios and is consequently designated as an important feature in electro-optic device design in view of polarization independence or polarization rotation requirements.