Structure and microwave properties analysis of substrate removed GaAs/AlGaAs electro-optic modulator structure by finite element method

Abstract

In this paper, structure and microwave properties of a substrate removed GaAs/AlGaAs traveling wave electro-optic modulator structure were analyzed and simulated by using the finite element numerical technique for lower loss, simultaneous matching of optical and microwave velocities and impedance matching with 50 Ω. The effects of core layer thickness, claddings thicknesses, and width of the modulator on the microwave effective index n_m were investigated, the characteristic impedance Z_C, the microwave losses α, and the half-wave voltage-length product V_πL were calculated. The results of the simulation suggest that the electrical bandwidth of 22 GHz and the optical bandwidth of 48 GHz can be obtained for fully matched, lower loss structure, which correspond to a 13 V·cm drive voltage.

Keywords

electro-optic modulators / finite element method (FEM) / integrated optics / optical communication equipment

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2014 Higher Education Press and Springer-Verlag Berlin Heidelberg