Multiphysics modeling and analysis of integrated optical E-field sensor for sub-nanosecond intense electromagnetic pulse measurement

A novel integrated optical electric field sensor especial for sub-nanosecond intense electromagnetic pulse measurement is designed and analyzed considering multi-physics coupling condition in COMSOL software. Sensor element combined tapered antenna and electrode is analyzed in XFDTD software. The model is verified by setting maximum mesh size based on the restriction in electromagnetic wave vector. The multi-physics coupling method is proposed. Simulation results verify the sensor measurement range can reach 1000kV/m with good linearity. R-square of the fitting curve of the 1000 kV/m measurement range is 0.9946. Frequency response is analyzed utilizing the time domain response result of the element in XFDTD and waveguide in COMSOL. The frequency response of the sensor ranges from 1 GHz to 20 GHz with less than 3 dB deviation.