A Polarimetric Interferometer Based on Composite Optical Waveguide for Refractive Index Detection

A sensitive interference refractive index sensor based on composite optical waveguide (COWG) was developed. Sol-gel technique used to prepare TiO2 sol, and the film fixed surface of single-mode potassium ion-exchange (PIE) (OWG) by dip-coating annealing treatment fabricate an device. The between zeroth-order transverse electric (TE0) magnetic (TM0) modes laser beam which transport in COWG caused phase-difference change (Δ) output light signals. Refractive sensitivity TiO2/PIE chip examined injecting aqueous NaCl solutions distilled water turn detect its Δ. Experimental results show that, for is SRI = (573.09 × 2π)/RIU ranges 1.3386~1.36. sees advantages high sensitivity, compact size, simple fabrication, as well low cost.