Electro-optical intensity and phase modulations of a racetrack micro-resonator based on a LiNbO3-silicon hybrid waveguide covered by electro-optical polymers

Abstract

Rapid developments of 5G have led to ever-increasing demands for high-performance modulators. To improve modulation performances, an electro-optical (EO) modulator based on a racetrack micro-resonator (RMR) covered by EO polymers is demonstrated. The RMR-based EO modulator consists of LiNbO3-silicon hybrid waveguides (LSHWs) and an EO polymer coating. The finite element method (FEM) is used to obtain the transmission and modulation characteristics of the LSHWs-RMR. The simulation results show that the EO modulator based on the LSHWs-RMR has an EO wavelength tuning (λEO) of 32 pm/V and a phase shift per volt (φEO) of −0.0376rad/V for the quasi-TE mode. For the quasi-TM mode, there is a λEO of 40 pm/V and a φEO of −0.0350rad/V. The calculated Vπ⋅L for the quasi-TE and quasi-TM modes are 0.45V⋅cm and 0.40V⋅cm, respectively. The proposed EO modulator based on the LSHWs-RMR has potential application prospects in coherent optical fiber communication systems, comb generators for generating multiple optical frequencies in dense wavelength division multiplexing optical fiber systems, and electro-optical frequency shifters for laser beams.