Three-Dimensional Optical-Electrical-Thermal Multi-Physical Analysis and Optimization in Thin Film Lithium Niobate Based Electro-Optic Modulator

We demonstrate a three-dimensional (3D) investigation of optical-electrical-thermal multi-physical effect in thin film lithium niobate based electro-optic on-chip modulator. For the first time, the 3D visualizations of the optical field, the microwave field, and thermal field are carried out. The obtained key performances of modulator such as half wave voltage and modulation bandwidth are basically consistent with the reported experimental data. This report emphasizes on the thermal effect investigation such as the heating dissipation and steady-state temperature distribution. Besides, the dependencies of heating and temperature increment on the microwave frequency and the electrode gap are discussed quantitatively, and optimization of the modulator design is then presented from the perspective of thermal effect.