Theory and modelling of optical waveguide sensors utilising surface plasmon resonance

A theoretical analysis of the phenomenon of excitation of surface plasma waves in integrated-optical waveguide structures is carried out. Rigorous approach to analysis of light propagation through a waveguide structure with a thin metal overlayer supporting surface plasma waves is formulated using a bi-directional mode expansion and propagation method. It is demonstrated that because the back-reflections in the structure are very weak and most of optical power is transmitted by only a Limited number of modes of the sensing structure, the method can be considerably simplified. (C) 1999 Elsevier Science S.A. All rights reserved.