Design and analysis of photonic crystal fiber plasmonic refractive Index sensor for condition monitoring of transformer oil

This paper presents an octagonal photonic crystal fiber based plasmonic refractive index (RI) sensor using graphene to measure the moisture content in transformer oil. For better insulation, moisture content in transformer oil needs to be measured, as the moisture content degrades the insulation property of the oil. Basically, the proposed sensor is able to detect the change in RI of the oil as the moisture content changes the RI. This work is numerically simulated by a finite element method-based simulation tool and the simulation results are processed using a MATLAB environment to understand the performance. Using the proposed sensor, the maximum possible amplitude sensitivity can be obtained as 31,240 RIU-1 and 30,830 RIU-1 for the x- and y-polarized modes, respectively. Besides, the proposed sensor has also found the figure of merit (FOM) to be 5,000. Both the results are found to be highest to date (to the best of my knowledge). The novelty of this work is the idea of measuring the moisture content of transformer oil using graphene plasmonic RI sensor, the high FOM, and the highest amplitude sensitivity. (c) 2020 Optical Society of America under the terms of the OSA Open Access Publishing Agreement