Cascaded refractive index and corrosion sensors in a D-Shaped optical fiber using LMR and SPR effects

Abstract

This article presents the proposed structure and simulation results from analytical modeling of a refractive index sensor and a corrosion sensor in a D-shaped single-mode optical fiber using the lossy mode resonance (LMR) and surface plasmon resonance (SPR) effects. The combined sensor consists of two cascaded D-shaped sensor regions. The first, a bilayer of titanium dioxide - aluminum, operates under LMR condition, while the second, a bilayer of gold - titanium dioxide, operates under SPR condition. The sensors are interrogated by transmitted light at 1310 and 1550 nm, in TE and TM modes. Sensor sensitivities and operating ranges are presented.