Design and comparison of single-mode planar and ridge type electro-optic waveguide modulators

摘要

Electro-optic waveguide modulators utilizing phase retardation of two orthogonally polarized optical modes in LiNbO3and LiTaO3waveguides have been designed taking into consideration the optical field distribution in the waveguides and the electrical properties of the electrodes. The analysis has revealed that a driving-voltage to frequency-bandwidth ratio of 1 V/GHz is attainable at the wavelength of 1.05 μm using presently available embedded and ridge waveguides. Improvement in waveguide fabrication techniques may reduce the ratio by at least a half. Thus, LiNbO3and LiTaO3waveguide modulators are considered to be promising candidates for practical application to single-mode optical-fibre transmission systems of higher than 1 Gbit/s