Voltage Controlled-Electrooptic Directional Coupler with Parallel Electrodes.

Zaghloul, A.

doi:10.21608/bfemu.2020.131674

Voltage Controlled-Electrooptic Directional Coupler with Parallel Electrodes.

Document Type : Research Studies

Author

A. Zaghloul

Assistant Professor., Electronics and Communications, Faculty of Engineering, Zagazig University., Zagazig., Egypt.

10.21608/bfemu.2020.131674

Abstract

An algorithm is presented to find the effect of controller voltage, orientation of the crystallographic axes (Z-cut and X-cut) and types of the two cores electrooptic materials on both coupling coefficient © and power transferred between two adjacent rectangular electrooptic waveguides coupling coefficient is calculated by mixing effective index method (EIM) with coupled mode theory (CMT). The electrooptic material is treated as isotropic material with very thin metal electrodes. The applied voltage induces a change of refractive index of waveguides cores and so, there are changes of both the coupling coefficient and the difference between propagation constant of the two waveguides (∆ᵝ), coupling coefficient between two dissimilar electrooptic materials becomes very large than that between two similar electrooptic materials.
Maximum coupling coefficient is occurred between LiTaO₃ and BaTiO₅. Change of the coupling coefficient depends upon the optical polarization (E^x_pq or E^y_pq) and the operating wavelengths (λ).

Main Subjects