Long range surface plasmon resonance sensor based on side polished fiber with the buffer layer of magnesium fluoride

Abstract

In this paper, a theoretical analysis of figure of merit (FOM) of a surface plasmon resonance (SPR) sensor with a buffer layer of magnesium fluoride has been carried out. While the FOM is the ratio of sensitivity and full width at half maximum and it is the measurement index for the SPR performance. The numerical simulation is based on side polished single mode fiber SPR sensor with the 66.5 μm residual fiber thickness and Drude model of metal with the 50 nm gold film thickness. Meanwhile, the comparisons for traditional surface plasmon resonance sensor, symmetrical surface plasmon resonance sensor and long range surface plasmon resonance sensor have performed differently for the FOM. The effect of sensitivity, full width at half maximum and transmittance depth has also been studied. All these studies, lead to a significant analysis to achieve the best possible design of a fiber optic SPR sensor with maximum FOM while the thickness of buffer layer is 100 nm. This design is expected to play an important role on chemical sensing and biological sensing.