Broadband Integrated Optical Waveguide Current Sensor Based on a Magneto-Optical Thin Film

Broadband transient current measurement is a basic research method in many engineering fields. Optical integrated current sensor has the advantages of small size, anti electromagnetic interference and high precision, which has become a major trend of current monitoring. However, the existing optical current sensing methods have great challenges in broadband, wide amplitude and volume miniaturization. In this paper, a new high-performance magneto-optical energy coupling sensing method based on silicon photons and magneto-optical materials is studied, and an integrated optical waveguide current sensor based on a magneto-optical thin film and a double-ring assisted Mach-Zehnder interferometer is proposed. The energy coupling between the micro-ring resonator and the magneto-optical thin film is achieved through the magneto-optical nonreciprocity effect, and the current information is obtained by modulating the output light intensity with the Mach-Zehnder interferometer. The experimental results show that the sensor has a good linearity and a large dynamic measurement range. The measurement frequency range is from10 Hz to 13.56 MHz, and the sensitivity is 2.183 mV/A. This work seeks to promote the development of optical broadband current sensors on chips.

Automated summary

This paper studies an integrated optical waveguide current sensor based on silicon photonics and magneto-optical materials, achieving energy coupling between the micro-ring resonator and the magneto-optical thin film through the magneto-optical nonreciprocity effect, and obtaining current information through a Mach-Zehnder interferometer.