Effects of Nonrectangular Electrodes and Temperature in LiNbO Based Optical Modulators

ABSTRACT

The effects of electrodes geometry and temperature on high frequency RF transmission characteristics are simulated versus LiNbO₃ layer thickness, inter-electrode gap, and optical waveguide parameters. On the other hand, we focused on the optimization of the electro-optic modulator parameters where the effective index plays an essential role in the evaluation of the bandwidth structure. Therefore, a theoretical analysis of the capacitance, the characteristic impedance and the effective index determine how to increase the bandwidth. The study of the variation of the effective index versus temperature shows a net drift, which affects the quality of transmission. Moreover, an approximate estimate of Sparameters shows the sensitivity of reflection and transmission ratios upon temperature.

The interaction optical-microwave is also analyzed using Laplace equation and Finite Element Method.

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