High-sensitivity fiber current sensor coated with UV and conductive silver adhesives

Abstract

This work demonstrates a highly sensitive fiber-optic current sensor based on a Mach–Zehnder interferometer. The sensing structure is fabricated by splicing a multimode fiber-no-core fiber-multimode fiber segment between two single-mode fibers, followed by successive coatings of ultraviolet (UV) glue and conductive silver adhesive to enable current response. Experimental results indicate that Sensor 2 exhibits a current-squared sensitivity as high as −145.1553 nm A−2 in the 0–0.32 A range, roughly 11.3 times higher than that of Sensor 1 without the UV glue coating. Temperature cross‐sensitivity is effectively eliminated through integration of a fiber Bragg grating. Owing to its high sensitivity, simple fabrication, low cost, and excellent repeatability and stability, the proposed sensor thus provides a practical and reliable solution for current monitoring in real‐world applications.