Theoretical understanding of an alternating dielectric multilayer-based fiber optic SPR sensor and its application to gas sensing

In the present work, a detailed theoretical analysis of a surface plasmon resonance (SPR)-based fiber optic sensor with an alternating dielectric multilayer system is carried out. The dielectric system consists of silica and titanium oxide layers. The effect of critical design parameters on the sensor’s sensitivity and detection accuracy is studied. The results are explained in terms of appropriate physical phenomena, wherever required. Based on the analysis, a new design of a fiber optic SPR sensor for gas detection is proposed. The analysis of such a gas sensor is carried out for four metals separately for a clear understanding. The proposed gas sensor is able to provide reasonably high values of all the performance parameters simultaneously, as required for an efficient detection of gaseous media. 1 Author to whom any correspondence should be addressed. New Journal of Physics 10 (2008) 023039 1367-2630/08/023039+12$30.00 © IOP Publishing Ltd and Deutsche Physikalische Gesellschaft