Novel electro-optical modulator utilizing GeO₂-doped silica waveguide

Abstract

In order to achieve a modulator with broad bandwidth and perfect impedance match, a novel electro-optical modulator based on GeO₂-doped silica waveguides on silicon substrate is designed. The finite element model of the whole electro-optical modulator is established by means of ANSYS. With the finite element method analysis, the performance of the novel modulator is predicted. The simulation reveals that the designed modulator operates with a product of 3 dB optical bandwidth and modulating length of 226.59 GHz·cm, and a characteristic impedance of 51.6 Ω at 1 550 nm wavelength. Moreover, the calculated electrical reflected power of coplanar waveguide electrode is below −20 dB in the frequency ranging from 45 MHz to 65 GHz. Therefore, the designed modulator has wide modulation bandwidth and perfect impedance match.

Keywords

optical modulator / GeO₂-doped silica / finite element method

References

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