An efficient approach for investigating surface plasmon resonance in asymmetric optical fibers based on birefringence...

We have analytically investigated the polarization dependence of surface plasmon resonance in fiber structures having strong asymmetry. From our simulation experiments it is found that the resonance wavelength coincides with the zero-birefringence point of two degenerate modes, consequently demonstrating a new approach through which one can accurately locate the resonance peak of the system without having to analyze the loss spectrum. Results obtained using the new technique also reveal better performance in terms of accuracy and computation efficiency. Application of this approach in the analysis of refractive index and pressure sensors based on the single core D-shaped and symmetric multiple air-hole fibers respectively is presented as a demonstration. The proposed technique, which primarily involves the search of zero-birefringence point, may be generalized for the study of other plasmonic waveguide structures.