ELECTROOPTICAL AND OPTICAL EVALUATION OF PB(ZR, TI)O-3 THIN-FILMS USING WAVE-GUIDE REFRACTOMETRY

Prism-coupled, waveguide refractometry was utilized to independently m onitor electric-field-induced changes in the extraordinary and ordinar y refractive indices of a Pb(Zr0.53Ti0.47)O-3 (PZT 53/47) thin film. U nder an electric field, applied normal to the film plane and correspon ding to saturation of the electric polarization, the ratio of the extr aordinary to ordinary refractive index change, Delta n(e)/Delta n(o), is found to be -4/1, contributing to a net birefringence change, Delta (n(e) - n(o)), of - 0.021. The technique thus accesses both diagonal a nd off-diagonal elements of the electro-optic response tenser describi ng the macroscopic behavior of the polycrystalline film. In addition, the widths of the waveguide mode reflectivity minima were sensitive to variation in the microstructure of several PZT (40/60) films indicati ng that the refractometry technique can provide information helpful in evaluating the optical quality in these films.