Design and Analysis of Broadband LiNbO3 Optical Waveguide Electric Field Sensor with Tapered Antenna

The three-dimensional (3D) simulation model of a lithium niobate (LiNbO3, LN) optical waveguide (OWG) electric field sensor has been established by using the full-wave electromagnetic simulation software. The influences of the LN substrate and the packaging material on the resonance frequency of the integrated OWG electric field sensor have been simulated and analyzed. The simulation results show that the thickness of the LN substrate has a great influence on the resonant frequency of the sensor (approximate to 33.4%). A sensor with a substrate thickness of 1 mm has been designed, fabricated, and experimentally investigated. Experimental results indicate that the measured resonance frequency is 7.5 GHz, which nearly coincides with the simulation results. Moreover, the sensor can be used for the measurement of the nanosecond electromagnetic impulse (NEMP) in the time domain from 1.29 kV/m to 100.97 kV/m.

Automated summary

A 3D simulation model of a LiNbO3 optical waveguide electric field sensor has been established using full-wave electromagnetic simulation software. The simulation results show that the thickness of the LN substrate significantly influences the resonant frequency of the sensor. A sensor with a substrate thickness of 1 mm was designed, fabricated, and experimentally verified to be capable of measuring electromagnetic impulses in the nanosecond range.