Miniature Micro-Ring Resonator Sensor With Electro-Optic Polymer Cladding for Wide-Band Electric Field Measurement

With the development of Internet of Things technology and artificial intelligence, the electric field sensor is required to be miniaturized, high performance, and low cost. At present, the commercial use of electric field sensing technology is facing several limitations, such as dynamic range, bandwidth, size, and signal-to-noise ratio. In this paper, a novel integrated waveguide wide-band electric field sensing solution is proposed. Based on the evanescent field and electro-optic effects, the high efficiency electro-optic energy coupling between the micro-ring resonator and the electro-optic polymer film is realized. Further, the information of the applied electric field is obtained by detecting the output light intensity of the Mach-Zehnder interferometer. The sensor can measure the electric field efficiently over a wide frequency band (50 Hz–13.5 MHz) and maintains good temperature stability. The sensor is small in size, simple in structure, low in cost, and easy to integrate. In addition, the sensor has the capability to realize the functions such as atmospheric electric field monitoring and lightning warning, providing a technical foundation for the construction of the Internet of Things.