Bismuth Sulfide nanoparticle doped optical current sensors with enhanced Verdet constant

Abstract

Magneto-optic current transformers (MOCT) are commonly used for measurement and protection purpose in high voltage power systems. Higher Verdet constant is desirable for increased resolution of the current sensor. In this work, an enhancement in the Verdet constant was demonstrated for bulk silica glass doped with Bismuth Sulfide quantum dots at very low AC magnetic fields. The measured values showed an enhancement of up to 3.6 times that of the original undoped blank glass host. The glasses were optically characterized using UV-Vis spectroscopy and then tested for magneto-optic sensitivity. The current sensing characteristics were defined with respect to the applied magnetic field and the rotation angle. The Verdet constant was determined by using a lock-in method that included a change in relative intensity at the detector.