Study on Sensitive Current Sensing Base on All-fiber Mach-Zehnder Interferometer

摘要

A direct current sensor based on all-fiber Mach-Zehnder interferometer is demonstrated in this paper. The phases of interferometric lights in the interferometer is modulated by heat effect when current flowing through a thin metal tube. The characteristics of current sensing are studied experimentally. Adopting the wavelength scale method, in the case of elimination of environmental perturbation, the wavelength changing range is 32nm when the current changes from 0 to 1.8A. The shifting wavelength is linear to the power and the linear fitting is 0.9987. The tuning efficiency is approximately 19.47nm/W.